Posted 03 October 2012 - 19:46
Yes, definitely! At least if you're into that kind of thing. I completely recognize that plenty of people want to buy a phone and just use it without screwing around with it. I, however, quite enjoying trying new ROMs constantly. On nearly every device you can get some sort of an AOSP ROM (Android Open Source Project, basically plain vanilla Android without manufacturer's UIs and bloatware) that's likely make it much faster than it was before, give you access to newer versions of Android than the manufacturer has released, unlock or improve features, etc. I have an HTC One XL (AT&T One X), and it get official builds of most of the main ROMs such as CM10 (pure AOSP with just a few tweaks here and there), AOKP (usually based off CM10, but with a few more tweaks, my personal favorite), MIUI (an iPhone-esque type ROM. Clean, simplified, albeit a bit boring), and ParanoidAndroid (CM10 with per app DPI settings so you can run things in "tablet mode". Looks good on high res screens). The SGS3 is very developer friendly as well since it came with an unlocked bootloader. Of course if you want to go a little cheaper, there's always the Nexus phones like the Galaxy Nexus which come with AOSP already and easily rootable and unlockable.
The rooting/custom ROM community is massive. Take a look at what devices you like, then look them up at xda-developers.com to get an idea of what kind of third party software and ROMs are available for it.