Rear-Projection TVs - Life Expectancy

[Ruby]

I bought a Toshiba 43 inch 4:3 rear-projection TV in August 2000. I use it for about 4-5 hours every weekday and more on weekends. I bought a rear-projection for the obvious reasons (ie. size of picture) but I can't wait to get a CRT set again for the picture clarity. However, I don't think the wife will be to happy if I try to replace my current TV unless it has reached the end of its useful life.

So my question is this; how long does the average rear-projection TV last before it reaches the end of its useful life ie. a bulb needs replacing or something?

[lurcher]

Bought mine also in Aug 2000, new bulbs replaced recently.
Similar useage. I am sure there a people who have had RP sets longer without any repairs tho.