I have a Samsung 50" 1080p in the living room and Panasonic 50" 720p in the bedroom. Those are the 2 brands you want to go with for plasma and they are basically equal. My Sammy is about 4 years old and still looks great. At this point I would probably go with an LED tv, the blacks are much closer to a plasma than they used to be.
If you are only going 40" then I would go with a cheaper TV and a better sound system. Then when you get back home you can reuse the sound system even if you end up going with a bigger TV. I got a Denon receiver a year ago and it is amazing, get one with the audyssey system, you can tune every speaker how you want. I run Pold speakers and I am sold on them. I got some cheap from newegg on black friday and I just saw they were on sale again last week. I have had many different kinds of speakers (infinity, JBL, bose) and love the Polks.
You could get these and use them as fronts until you get in a bigger place, then switch them to rears:
http://www.newegg.com/Product/Produc...Audio-Speakers
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