[T-Mobile Samsung Galaxy S II SGH-T989] jets76:
So I went ahead and ordered a Mugen Power 3900mAh Extended Battery HLI-T989XL and received it yesterday. I am on the road most days and having to worry about battery life is not a gripe I need. The option of carrying an extra battery around turns me off mainly because;

• It's one more thing I will have to do everyday...charge it

• I'd need to buy a separate charger

• I don't want to swap batteries near the end of the day, seems pointless

• Remember where I leave it, remember to charge it, remember to bring it to work. I don't want to remember more stuff than I have to; I can't remember what I ate yesterday.

I have to say that I am impressed with this battery and battery door with kickstand. As great as having a thin phone is, I have already dropped or had it slip out of my hands a few times. You can see in the photo where it got dented near the mic. The chrome trim around the phone and it's form factor on cool mornings had me really concerned about dropping it again and again as it was quick to slip around. I find that the phone is much more comfortable in my hand now with the added surface to hold...even if my phone does look like it ate an iPhone for breakfast. I measured and the phone grew in thickness from 11mm to 16mm after adding the battery and case from Mugen Power. I read about peoples complaints that it makes the phone way to big etc...then turn around and buy a bulky-ass case to tote it around in and it's just a big. Cracks me up. I digress; the bit of added weight was less than I anticipated and it feels really snug in my grip. Perhaps the weight difference isn't as profound because I am already used to the small weight bump from the Galaxy Nexus extended 2100mAh battery I have been running in it (that fits after sanding it down a bit LOL).

As far as usage? I charged it for 12 hours and started using it at 09:00 today. At 22:00 I still had 35% left and I am so happy. Usually I need to plug it in around 17:00 or 18:00. After charging it for 12h the following 4 nights I should start to see even better longevity according to the paperwork I got with it. I was reluctant to buy the Seido brand extended battery because they always were poor performer when I used their Blackberry batteries in the past. Also because they made it look clunky and awkward-out of place on the phone. This one from Mugen looks like it could be an stock product because it flows well and I like the look of it. With this, I am confident I won't have to decide if I want to play a game or watch a video and if I will have enough power to get through the day.

I am very happy with this product but I have to mention something strange that I noticed. After installing this battery the phone began to freeze and lag like crazy. Sometimes it would not wake when the screen shut off either. Pissed me off I tell you. I thought what the hell could be causing this?? I am running Jugs 5 with Gideons -75 UV script. Hmm..battery....undervolting...I thought about it and I thought let me try flashing the other -50UV script and see what happens. Problem solved! Very weird but true. Something about this battery caused this but I have no clue how.

Lastly, I am spring clip guy; I buy them for all my phones but there are not much options for this model FFS. Anyways, the phone I replaced was a HTC Desire HD/Inspire. I had the Seidio 'Surface' (adds 1mm to exterior of phone) spring clip holster lying around and go figure-the G2SX fits pretty good with the extended battery :D The only thing is putting it back in is a two-handed deal as the top clip comes down too much since the HTC is a smaller phone. Just gotta lift it a bit and pop the phone in until I get me a new holster. Getting back to options, some may be aware that the TMO GSII/G2SX only have Seidio's 'Active' case and spring clip holster available right? See the way I figure it is if the active case adds 2mm+ to the exterior of the phone it should fit with this extended battery for sure with no case on it. I will post my findings after it arrives.

Stock 11mm thick, Extended battery 16mm thick. Here are the shots:

In the HTC Desire HD/Inspire Surface holster.

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