Yea I would try the plasma if you're using it for games and movies. I have a Samsung 58" C7000 plasma in my office for games. With the game mode on you have no input lag or response time issues, and blacks are awesome of course.
Also, compared to my 2009 PN50B650 50" plasma which will get image retention after only a couple minutes on something like a ESPN scoreboard, the image retention is almost nonexistent on the 2010 model. You would really have to abuse it to get any burn-in.
The biggest downside to the Samsung plasmas is "the buzz". All plasmas will buzz to a certain degree, but many of them emit a rather loud buzzing noise that Samsung claims is normal. Some you can only hear it a foot away from the tv which is fine, but others you can hear it from 12ft+ away. 50" or less panels are usually ok though, because they only have one power board.
Depending on your age, you may not even be able to hear the buzz whatsoever though. But if you can and it bothers you, buying locally should ensure you can exchange it or return no questions asked.
Far as local deals go, I'd check out a site like slickdeals.net. At 9.75% sales tax here, I take the risk of online only. Samsung's warranty is decent though, I got a brand new tv direct from them cause mine had one dead pixel. Took about a month all said and done, but they replaced it no cost to me.