I've been using my AE900U a lot more than I thought I would as I love it and hopefully won't have to replace the bulb for quite a while but I got to thinking since I'm coming up on 600 hours of use. When It comes time to replace the bulb is it something I can do myself or is it something you have to send it off for? I read somewhere that it's reccomend to have a professional do it. I think it was in the manual or something. What is involved? Do most people do it them selves or have someone else do it? How much would it cost me to have someone else do it?

You can do it yourself. It is very easy. Be sure you clean the fliter often it will make the bulb last much longer. Read the instruction manual where you will find directions on how to replace the bulb and reset the timer when necessary. You should be able to get about 3000 hours on the lamp in the low setting.

I read somewhere that it's reccomend to have a professional do it.

I'm guessing that was written by a "professional." :)