I've seen the epson 8350 and the epson 9700. I have not seen the benq, so I can't compare it. From what I've read the 9700 and the 8700 are basically the same projector. The 9700 has the anamorphic lens option and a black case is the only difference.
I thought the 9700 was very good. They had it in a dedicated show room (theater) and even with the lights on it performed pretty well. It's what sold me on getting a projector.
I saw the 8350 also. It was at a private residence. I thought it was quite nice as well. For being my first projector I could've definitely been fine with it. I didn't see it perform on a lot of dark scenes, but based on my short viewing, it was a nice projector for the money.
I ended up going with the HD250 by JVC. I got suggested this projector by Benito. It's a little bit more than what you can get the 8700 for, but I you told me what your budget is. Call Benito and he might be able to help(I'm in no way affiliated with AVS, outside of being a customer).
What I've read about this projector showed it to be a more reliable product from a company with a track record for excellent projectors. The epson threads cautioned me a bit. I have not read many complaints about the HD250. One where someone was having an issue getting a replacement, but he was satisfied in the end.
I think the HD250 is an awesome projector. I recommended to my brother that he get one for his theater as well. When he saw it, he agreed. My brother likes nice things, as I do (though his budget was much higher).
You also only have a little while before CEDIA, so you could always wait and see if something new comes out. I'm new to the projector world, but I've done a fair amount of research, and it lead me to the JVC. I thought the Epsons were both fine projectors as well. Happy hunting