The only issue with these things is that all that video switching, surround sound processing, and THX certification all costs licensing money that doesn't go into the product. If you actually need the multi-channel outputs and all the rest then sure, but if they are just being used as stereo amps, then the value becomes questionable. Usually a $200-300 Onkyo stereo receiver sounds just as good as a $600 Onkyo surround A/V receiver.

I agree. It was the cheapest option I had though while my main amps need repair. I say it performs similar to m45 sound wise in my opinion.

Don't think either are THX certified though. But that's OK. There are other things George Lucas did better and eventually fucked up more over the years. Like Jar-Jar Binks.

THX certification on receivers is mostly nonsense anyway. It calls for an 80hz high pass crossover - big deal, every receiver made in the last 15+ years has that anyway. Aside from that, there's very dubious SPL requirements in a given space that I'm sure can be greased by the manufacturer.

What you actually "get" is a THX Cinema surround mode, which sounds like garbage, and so called Re:EQ, which is basically a treble "off" switch. At least that's what you got the last time I had an A/V receiver, which is admittedly many years ago. I'm not sure if it's any better now.

Yup. Regarding the cheapest option, I actually have the HTR-6160 which is the RX-V663 but could be had like $50 cheaper cuz the name.

At the time I bought, both Yamaha and Onkyo were updating their lines. Seems to happen once a year. Therefore discounts were appreciable. The SR606 and the HTR-6160/RX-V663 where the same price after discount. Sonics were nice on both with the very slight differences I described.

The two things that tilted me toward the RX-V663 where the temperature and the fact that it had 7.2 pre-outs. This sounded appealing if I decided to upgrade amp and speakers down the road. On the other hand, the SR606 had more HDMI inputs, but I figured I didn't need that many anyway (or might as well add a switch).

On paper from another side the RX-V663 looked better on distortion upto about 100W/Ch. But the Onkyo was able to deliver more watts before running out of juice (5 & 7 channel, 2 channel did better on the Yammy apparently).

http://www.soundandvision.com/content/yamaha-rx-v663-av-receiver-measurements

http://www.soundandvision.com/content/onkyo-tx-sr606-av-receiver-ht-labs-measures

Don't think either are THX certified though. But that's OK. There are other things George Lucas did better and eventually fucked up more over the years. Like Jar-Jar Binks.

The heat issues on the older onkyo before the models that started using hdmi inputs  were not much an Issue due to them using hefty heatsinks. Even though my onkyo is considered class a/b design it still runs fairly warm. The newer models I don't know.  I know Yamaha switched to class d in most of there newer models to make them more efficient same as Pioneer elite models I think.

Onkyo issues I ran into was there video switching issues with hdmi and the hdmi boards failing due to faulty firmware but apparently fixed the issue in current models.  Never read any complaints about the audio part of them and were well regarded for their audio performance and were top pick right next to denon or yamaha if music was priority and for all around use.

My 602 is older with only component inputs. Only negative thing I read on mine was it running fairly warm and could not convert composite to component and the auto mic speaker calibration was god awful. But of course I don't need the video inputs  and I hate using any form of eq so those issues I read was not problem with me. The digital inputs and analog inputs work perfectly and have no problem setting things up manually.

I also don't use the video upconversion of my Yammie. I need to play with its equalizer though. See what I get, but haven't yet.