If I may ask, I own a MT4G, how do I tell what screen type I have?
Download the app "terminal emulator" from the market. open it up and type DEMSG and press enter. a bunch of stuff will show up. scroll to the very top and at the bottom of that top part there should be a line that says panel type=1 or panel type=2 if you have 2, you have the good one. if you have 1 then it is the bad one.
just an fyi, my suggestion is if you can to get out of owning that mt4g ASAP unless you plan on rooting and flashing a custom ROM. it slows down and starts lagging horribly after a while. notification bar doesn't pull down when requested, random hang-ups and lag whenever you do ANYTHING. I did accept the G2 that tmobile offered me as replacement for the mt4g and it works great. battery life on the stock rom isn't that great (but then again neither is the one on the mt4g) but with the virtuous g-lite rom on it the battery life is top notch...
also, the screen looks GREAT on all models and not just a few like on MT4G.
if it turns out you have the bad screen I would definitely contact tmobile and see what they can do for you. most likely just keep replacing your phone like they did with me. maybe you will luck out and get a good one ^^
good luck and let me know if i can be of any further help.
EDIT: if it convinces you any more to try and go for the G2 like i did, I can say that the G2's performance is almost identical out of the box. And after I put virtuous g-lite on it and was able to overclock the processor to 1.2ghz (as opposed to the 800 that comes stock and the 1ghz that is in the mt4g...the processors are the same other than the clock speed) the performance (at least according to quadrant and neocore) blow the mt4g away. still nothing you can do about the slightly less ram in the G2 but it doesn't make much difference (especially on g-lite which uses significantly less RAM than stock)...
EDIT2: http://forum.xda-developers.com/showthread.php?t=863679 there's an xda thread on it if you'd like more info