Now, with your speakers, it would be good to know what the impedance really is, as saying "compatible with 4 and 8 ohms" doesn't really tell us, though it is suggestive that it is really lower than 8 ohms. I read in a review that they are 6 ohms and a sensitivity specification of 89 dB. That would not be too difficult of a load, but if you play your system at deafening levels, you would want to get the most powerful receiver you can (just remember, though, it takes a doubling of power to add a mere 3 dB of SPL, so a small difference in power output is not likely to be noticed). Reading a bit further in the review, though, I see they have a minimum impedance of 3.5 ohms at 200 Hz. That is not good for most receivers these days, and you might want to get something that puts out a lot of power into 4 ohms.
Given that, you might be best off getting something like the Pioneer VSX-1015TX which retails for only $499, and can be had for less. It should be fine if you don't listen too loud, and depending on your other needs. At its price point, I don't know of anything better, or even very close, to its performance. You can read about it at:
http://www.pioneerelectronics.com/pna/product/detail/0,,2076_4153_209686388_tab=B,00.html?compName=PNA_ProductDetailComponent
(If you want to download the owner's manual and read it, you will need to register, but it is free.)
I am suggesting this receiver for a couple of reasons; first, it is great for the money, and second, it leaves you with enough money to buy a separate power amplifier for the front speakers if needed, which will take some strain off of the receiver.
