Disadvantages of Plasma Televisions
Since plasma television emit light using phosphorous materials, they are susceptible to screen burn-in. Screen burn-in happens when static screen images illuminate the same sections of phosphor for long periods of time, thus darkening the phosphor material and resulting in faint ghost images of what was displayed in the past. Static images with high contrast are particularly problematic. High contrast images have dark areas next to bright ones right next to each other. So, white letters on black background, for example are likely to cause burn in. But, yellow letters on a blue backgound are just as bad because a yellow pixel contains the blue and green of an RGB triplate, and a blue pixel contains just blue, therefore resulting in high contrast in green. The burn in problem was ubiquitous in CRT computer screens, leading to the advent of "screen savers". Plasma screens may be in danger of burn-in after about 15 minutes of showing the same picture. Many plasma televisions contain built in screen saving features, such as automatically moving the image by a couple of pixels every few minutes, or automatically reducing image contrast.
Plasma televisions tend to lose their brightness over time. A typical plasma television will lose half its brightness after about 25,000 hours of operation. This number varies by model. There is no fix for this problem, and once it's noticable you'll just have to buy a new TV. But the good news is that 25,000 hours will give you many years of normal nousehold use, and you'll probably want to get a new television for other reasons before it becomes a problem.
Plasma televisions are not a good match with high altitude operations. The low air pressure in high altitudes causes the relative pressure of the plasma gas to go up, increasing the stress on the plasma screen. This effect increases the power needed to run and cool the television, making cooling fan noises more noticable. Plasma displays typically start having trouble at about 6000 feet, but check the manufacturer's instructions for specific high altitude opperations recommendations for your TV