[Samsung Galaxy S9+ Accessories] meyerweb:
My reviews of four cases after using each over the last 3 days. Not real extensive use, but enough to figure out what's good and bad about each, and how I feel about them. None of them are my "ideal" case, so I'll undoubtedly be trying more and adding more reviews to this thread.

X-dorna Defense Lux (“Cabon Fiber”)

First Impressions: This case has a lot of good reviews (on other phones) online, so I thought I’d give it a shot. I’m not sure how I feel about it. The case material is very hard and stiff, with no soft padding at all. It seems to me it will transfer the energy from an impact right into the phone. There’s a reason football helmets, motorcycle riding jackets, and pretty much every other impact protection have a compressible liner: compressing that material absorbs energy that would otherwise go through to the head / body / whatever.

OTOH, the box says it’s “certified to survive a 10’ drop onto concrete. But what does that mean. Does the case survive a 10’ drop? How about the phone? Does it survive with no damage at all, or does minor damage that doesn't affect function count as "survived"? No details are provided. It also “exceeds mil-std-810G.” Which doesn’t mean as much as you might think: https://www.digitaltrends.com/mobile/phone-cases-military-drop-test-standards/

The truth is that none of these claims by manufacturers amount to much, because they're all self tested, and no details are provided.

The aluminum band seems to be more for style than function, because it doesn’t actually cover the parts of the case most likely to see an impact: the corners and edges.

Oh, and I put “Carbon Fiber” in quotes in the title because it’s really not a very good imitation of CF. It looks like exactly what is is: molded plastic.

https://xdorialife.com/products/galaxy-s9-plus-case-defense-lux?variant=360800059408

In use review: Disappointing. On the positive side, it has significant raised edges on the top and bottom to keep the screen safe when you set the phone face down. But that’s about it.

I’m still not convinced it offers as much protection as many less expensive cases. It’s also bulky, adding quite a bit to both the width and thickness of the phone. In fact, it’s by far the thickest of the cases I’ve tried so far. The added thickness makes it harder to get my fingers on the FPS in back, and I got some read errors with this case, and not any of the others. I have fairly small hands, and really feel the added bulk. The edges of the case contain sharp angles, rather than the rounded forms of most cases, and I found them pretty uncomfortable. The button action is pretty good, but stiffer than the other cases tested here. I’m going to see if I can send this one back.

Spigen Ultra Hybird

First Impressions: I had a similar case for my S7 Edge made by Ulack, which was one of my favorites. A hard, clear polycarbonate back surrounded by an impact absorbing TPU bumper, with addition corner protection in the form of "air bubbles" between the TPU and the phone. But the Spigen is disappointing in comparison, in multiple ways.

The Ulak case had raised “feet” in the corners of the back, which kept the polycarb off of whatever surface you laid it down on . The Spigen doesn’t. Put the phone down, and it’s going onto that clear plastic back. I suspect it going to get all scratched up very quickly. And even before putting it on a phone, the clear plastic back shows huge amounts of rainbow effect. Not impressed so far.

https://www.spigen.com/products/galaxy-s9-plus-case-ultra-hybrid?variant=570814824449

In use review: A mixed bag. The case looks nice, and the clear back shows off the phone, especially if you got something other than black. It’s narrower than the Caseology Parallax, so it’s easier for me to hold, but probably offers a little less impact protection as a result. It’s got raised edges at top and bottom for when you set the phone face down. They’re not as tall as on the X-doria or the Caseology, but should be good enough as long as you’re not setting the phone down on rough finished concrete. The button action is typical Spigen – very good. Oddly, the volume buttons are harder to press than the power button, but that’s not a real issue. My only real objection to this case is, as I mentioned in first impressions, that the clear back is going to end up getting scratched up pretty quickly, unless you always set your phone face down. The rainbows I saw with the case off the phone aren't visible when it's installed on a black phone, but I can't say whether they will be on a lighter one. Oh, and the back of this case is as much a fingerprint magnet as the bare phone.

Caseology Parallax

First Impressions: Similar to the better known Spigen neo-hybrid. Black TPU with a semi-rigid plastic band around the edge. In theory the plastic band should help distribute the force of an impact over a greater area, reducing the forces acting on the phone (like the hard shell of a motorcycle helmet). In reality, the band is so thin I’m not sure it makes much difference. But it certainly won’t hurt anything. The TPU isn’t as soft as some, but it’s certainly not as hard as the X-doria case. Probably a good compromise. The sides are thicker than some cases I’ve looked at, which is a good thing, but there doesn’t seem to be any extra corner protection. The box says it’s been “drop tested 26 times,” but without more data that’s meaningless. From how high? Onto how hard a surface? Did the phone suffer any damage in those drops? They don’t say.

The Caseology has one feature which none of the other cases offer. It has a sloping section below the FPS to, I guess, guide your finger to the sensor. I suspect this will reduce the likelihood of hitting the camera lens instead of the FPS.

https://www.caseologycases.com/products/galaxy-s9-plus-parallax-case

In use review: I like this case quite a bit. The TPU is a little thicker than the Spigen, which may translate into a bit better impact resistance. The tradeoff is that, if you have small hands, it’s a little harder to hold one-handed. The sides of the case are a little taller than the other cases, which may offer better protection if the phone lands on one side. They don’t interfere with the edge functions, either. Like the other cases, it has a raised top and bottom edge to keep the screen off whatever surface you set the phone down on. The button action is very good – every bit as good as the Spigen. This case, and the Ringke, have the opening for the flash and HR sensor in a separate little window from the cutout for the lenses and flash. That may help keep your fingerprints off the lenses. The slope to the FPS that I mentioned above, as it turns out, doesn’t help at all. I end up putting my finger on the slope, instead of the FPS, and then have to slide it up. The shorter cutouts on the Spigen and Ringke are better. But I could easily live with this case as a daily driver.

Ringke Onyx

First Impressions: Your basic “little black dress” of a case. Plain TPU, thinner and softer than the Caseology. But it’s very nice looking. I like the brushed metal look of the back. Should offer about as much protection as other inexpensive TPU cases without adding very much bulk to the phone.

https://www.ringkestore.com/products/galaxy-s9-plus-ringke-onyx?variant=6366033739803

In use review: It’s fine. If you value a case that doesn’t add bulk, this will do the job. The button action is the best of the four. It feels almost like you have no case on at all. Like the Parallax, it has a separate window for the flash and HR sensor, and the cutout makes the FPS easy to find and reach.

Conclusions: The X-Doria is a non-starter for me. Just too bulky for the protection it seems to offer, and uncomfortable to boot. The other three are all acceptable, depending on what you’re looking for. I like the look and feel of the Ringke Onyx the best, but it seems to offer the least protection. The Parallax probably offers the best compromise between bulk and protection, but the FPS opening is makes using the FPS more awkward than it needs to be. Finally, if you want to show off the back of your phone, the Ultra Hybrid seems fine, other than the issue of scratches. I probably wouldn’t choose it for a black phone, though.

Hope you find this useful.