New receiver

For $1,000, your friend could actually afford some separates: a preprocessor and an amp. In most cases, separates will handily outperform (sonically, not gimmicks) a similarly priced receiver.

Tell him to look for something like the Emotiva UMC-200 preprocessor and an Emotiva UPA-500 amp. Unfortunately, Emotiva has just recently discontinued these items, but they should be readily available on the 2nd hand market. And, because they come with 5 years warranties, the chances are very good that he could get a set still under warranty.

Another really good option would be the Sherwood PT-7030 preprocessor and an Emo amp. The Sherwood is a very good preprocessor that was last sold by Emotiva. It has all the bells and whistles you could ever want. Found one on FleaBay for $585 - Buy It Now:
http://www.ebay.com/itm/Sherbourn-PT-7030-AV-Surround-Preamp-Processor-/231670967313?hash=item35f0aa6c11

A real bargain setup would be this Outlaw 990 Preprocessor for only $280 Buy It Now:
http://www.ebay.com/itm/Outlaw-Model-990-Pre-Amp-7-1-Channels-Tested-Working-/391243873137?hash=item5b17f3bb71

You still need a 5-channel amp with this and those can be found on FleaBay or here on A'gon. Here's a nice Adcom GFA-7500 amp on A'gon for $450:
https://app.audiogon.com/listings/multi-ch-adcom-gfa-7500-5-channel-amplifier-price-reduced-2015-09-01-amplifiers-24551-forest-va

That amp will walk all over ANY amp you can find in a receiver!

There are many more choices for $500 and under. Long story, short: shop wisely and you can get a high performance system for mid-performance money...

-RW-

If high performance is important to your friend then R1's suggestion is a good one as you hit the $1000+ price range. If they're just looking for something that provides decent performance, convenience, and reliability, I'd look at Yamaha AVRs. They get relatively high marks for sound quality and I don't see people reporting problems with them, unlike Onkyo. Also, if it has enough features and power you may well get everything you need from a $500 AVR and maybe even less. Best of luck.

I pretty much concur along lines of Rlwainwright. Separates, yes, would be strongest sounding/performing option, sonics wise. Better amplifier with separates, like 95% of the time, by default - weak amps in ESPECIALLY lower priced AVR's. If not, then get the AVR and consider adding an outboard amp to that mix with AVR that has Pre-out's. If you can't - or don't want to - go with multiple boxes, and stay AV receiver all-in-one, then I suggest the most features, DEFINITELY WITH A ROOM EQ, 4K pass, 3D, switching, Bluetooth, connectivity, whatever, you can find in an AVR. Used market and refurb (warranty?) gets you MUCH more bang for buck, as this stuff depreciates down to $0.10c on the dollar from MSRP like nobody's business!! Believe it! Buy new, and you'll get less, weaker amps, and less power for your dollar (although lots of features for money these days, regardless, minus preout's) .
That all said, either way, I'd strongly recommend a warmer sounding receiver (crossed over to 100-80hz to a sub) and or amplifier in the mix, to balance the slightly cool somewhat analytical yet clear sonic character of Deftech's, such as Denon, NAD, Onkyo, Integra, Sherwood, and such for AVR's. For amplifiers, consider used Parasound, Classe, NAD, Integra, Sony ES, Outlaw(?), Bryston, etc, and similar, with warmer more forgiving tonality.
Million choices and directions. I'd prob steer away from Yamaha, Pioneer, cheaper Marantz, and even the otherwise superb HK's with your Deftech's, if I had to guess. Anthem?..might be tick bright, but then maybe not. Otherwise top tier AVR with EQ and refinement.
That's my experience of playing with this stuff for decades now. Some pieces may vary of course.
I'd recommend the

.... otherwise very good sounding Arcam, NAD, and B&K receivers but, again, NO EQ feature! (basically all rooms have bass problems you'll not fix from 20hz -300hz, and REQUIRE EQ'ing, PERIOD! ..too invaluable to pass up for hi-fidelity, IME).
You (he??) doesn't need 7.1 or Atmos, etc? Any 5.1-7.1 that fit on the list, are worth investigating, find reviews, or must give a try or sell if don't work out for you. Ok, I'm done now. ..

I have a Denon Avr 3100 and love it.