Denon 1909, Pioneer 91THX or 1018, or Onkyo

[jdlivestrong]

I really thought I had it all figured out and was going to order the Denon 1909 last night, but I didn't do it.

Well...now I'm leaning towards Pioneer, but I'm not really sure about the different models. The non Elite 1018 seems to be a great receiver, but I'm worried I'm going to want to upgrade again in 2 years.

I'm a little confused about the different Elite models. Can someone help me out a bit? What is the difference between the

91TXH
01TXH
92TXH
94TXH

models? Is that the order of good to best? What will one get me over the other? Or am I just over analyzing it and the 1018 will be solid. I'd really like to stay in the $500 range. Anyone see any great buys on these?

Thanks again.