[Galaxy S III Mini Q&A, Help & Troubleshooting] ggbhtg:
I've had the SGH-T599N since October, and, coming from the Samsung Admire with all its roms and mods and support, I've found having this phone to be, well, not as great.

My 2 main gripes with using internet on this phone, are that some sites I go to just don't quite work right with however MetroPCS/T-Mobile has their network setup, which I'll sort of elaborate on, and as of late, the, for lack of better phrasing, the peaking and subsequent slowdown of my internet speeds.

I'll start with the latter, since it's easier to explain, and because I tend to ramble, I'll state the question again before explaining:

1. Is there any way I can mod this phone to bypass automatic network speed capping?

I have MetroPCS's unlimited 4G plan, which ran at satisfactory speeds always at hundreds of KB/s until recently, which I assume is due to my speeds being capped out of over-usage. Considering I use USB tethering daily, this is not shocking. The thing is, I could get around that with my Samsung Admire thanks to this mod: http://androidforums.com/admire-all-things-root/563714-mod-data-governor-remover.html and by extension, this mod: http://xdaforums.com/showthread.php?t=888372

Considering that was a 2.3.4/Gingerbread OS phone, this is a 4.1.2 phone, and I've looked around both of these forum sites long enough to know not to do any phone modding without extensive research and to wait for the bugs to be sorted out by others, I dare not even get my hopes up about being able to do that with this phone unless there's a confirmed forum post saying I can. Before that, I also found ways around the limits of my 3G network area that's bogged down by the sheer number of users, as thanks to QPST, but falls under the same situation. I don't even want to try modifying the build.prop, much less those deeper settings on my own for risk of breaking/bricking the one and only phone I have and still need to have functioning fully for many more months. So far, I've only gotten around all this by turning my phone and maybe the mobile network on and off, because the slowdown lock takes a couple minutes of use to kick in.

2. Can I change the network settings of this phone in a productive/significant manner, via APN changing, QPST, ROMs, or other such mods?

I've done all of these before on my Admire without any permanent errors. I found that APN Manager Pro is too outdated for this OS, and have yet to try similar APN programs for risk of permanent network damage. I cannot currently recall any significant mention of using QPST on this phone, or even this OS, so I've not tried that. The only ROMs I know of are Unjustified Dev's, both of which break the video camera functionality, which I have to have working. The only thing I've even done to this phone is root it and put ClockWorkMod from this page http://xdaforums.com/showthread.php?t=2421743. I haven't even bothered with the odexed files, bloatware, and such yet because I mostly use this phone as just a camcorder, an internet modem, and of course, a phone.

I wonder about this because it may indirectly solve the first problem, but there's different issues as well...I'll just explain:

Now, I notice that some sites I try to use with this phone simply fail to work as properly as they would if I were using a Wi-Fi network, something that also happened with my Admire. Unfortunately I don't have many examples that I can share for one reason or another other than these following two, which luckily involve big name websites. However, they may or may not prove useless in the end, so I'll put them in spoiler tags to be easily skipped over to go on to the more important part.

When I tried to access Tumblr with my old phone's network, whether I'm on my phone or USB tethering to my laptop, it always refused to let me log in, meaning I had to go to a Wi-Fi network and log in from there first, and then, if I wanted to "ask a question" aka submit a message to any of the blogs/pages I'm following/subscribed to, they would always say that that function is not available "at this time", which basically means forever since it seems to involve some error on Metro's side that'll never be fixed. I know it's not some kind of script error on the browser end, because if I stop the page from loading at the right moment, the text input field would actually display and maybe even work, rather than be dummied out by some eternal error message that doesn't even come up if I were using any other network.

Also, on my current phone, when I try to upload a video to Youtube on an associate's account while tethering to my laptop, it refuses to upload, much less even recognizing that I'm trying to upload, as it stays at 0 percent. This is also circumvented by just using a different internet connection. This does not ever happen when I'm using my own account, however, and I've managed to circumvent by changing the browser's user agent or switching browser completely.

Now, I said that the above two examples may not even be relevant, because these may be issues only I can reproduce. For some sites, I manage to get around the issues with different web browsers and/or user agent or proxy settings, but I sometimes get Gateway Timeout messages and other such unavoidable errors on sites that imply server side problems, but don't come up when I use other internet connections. Because the issues vary from site to site, I'm only asking for a verified method I can test directly on the phone, on my own, to get around these problems.

That's should explain enough of, if not all of the issues I'm having network-wise. It might seem like rambling, but it's better for me to explain it all now than for someone that actually has the answer to come by only to be missing one crucial bit of info. In case it is just rambling, to reiterate:

I have the 4.1.2 OS phone SGH-T599N, the Samsung Galaxy Exhibit from MetroPCS, which has been rooted along with CWM, but no other modifications. I'm trying to modify the network settings, and need a confirmed method, not a guess, on how to go about it.