No problems with the LCD. Plasmas are touchy. It's hard to beat them for ultimate color saturation but that's only when they're new. They do have a shorter lifetime than the LCDs and they don't handle high altitudes that well because the screens distort from the lack of air pressure. After all, they pretty much are an electronic ballon.
There are some TVs used in RVs that are designed for higher altitudes but the majority of them are not.
The biggest issue with LCDs was the inability to crisply display motion. The LCD is really a series of LEDs that turn on and off real fast. The issue is how fast they can switch off without coasting to a stop. That tends you leave blurry pictures during fast action shots. The latest LCDs are really good at minimizing this but the quality varies greatly between the various models. LCDs are great and I'd go that way but I'd also be sure that I could see one operate first to see that the picture quality is what you want.
One last consideration when viewing TVs. Many of today's sets are high definition and the TV store sends an HD feed to them. Some sets are great in high def but really fall down in standard def. The Panasonic in my Bus is that way. It makes beautiful images in HD but when you feed it a composite or S video feed it's no where near that quality. Granted, it's not supposed to be HD quality but it's not as good as my older standard def TV was. This too varies from model to model so try to check them under both standard and HD feeds if at all possible. Bring a basic camcorder along with a pre-recorded tape and an RCA cable to plug in.