Thanks for the responses, Chuck!
I decided to get a G15 after buying and returning an LT150, because I was uneasy about having to live with the rainbows. At any rate, I'm way, way over budget now! I'd hoped that a longer throw lens (or some sort of attachment) would be in the hundreds of dollars, not the thousands. It constantly amazes me what some this stuff 'costs" (vs. what I personally think it's worth).
You are correct, after recalculating, the throw distance is about 23 ft, but that's still about 2-3 ft to short. Trading up to larger screen size or moving my screen closer aren't particularly appealing either. My theater was designed (by Dennis Erskine) to accommodate a 110" screen. It wouldn't be pretty or inexpensive to change. *Sigh*. I guess I'm just out of luck. I'll just have to see if the G15 runs as loud and hot as others have said and decide what to do from there. Thanks again for the suggestions!