Unfortunately, Yamaha has been playing a little loose with their lower level gear lately.
There have been a couple of bench tests that have shown poor performance especially into low impedance loads.
Fortunately, Accessories4Less uses Amazon to sell the units after yamaha has refurbished them.
Be sure the seller is A4L and you can rest assured that problems are unlikely and if they do happen, A4L will make good. Lots of guys here have used them (I have bought about 12 units from them by now - if they have what I want at a reasonable discount, that is what I am buying!
First off, I assume you want a stereo unit for the simplicity and because you will not have a TV connected, because otherwise, AVR's will generally provide better value.
Sticking with stereo, I think the best value in your budget is the R-S700 for $380 ($350 plus $30 shipping):
https://www.amazon.com/gp/offer-listing/B0044779G8/ref=olp_twister_child?ie=UTF8&mv_size_name=3&mv_style_name=0&qid=1509804448&sr=8-1
Next is the R-S500 for $228 ($200 plus $28 shipping):
https://www.amazon.com/gp/offer-listing/B0044779GI/ref=olp_twister_child?ie=UTF8&mv_size_name=2&mv_style_name=0&qid=1509804448&sr=8-1
The A-S301 should provide enough power for the Pioneer AJ towers under reasonable conditions, but you may decide to upgrade speakers down the road and I always like the idea of having power you never use which keeps your electronics operating with a nice reserve (everything, including heat sinks are designed to handle a heavier load).
I have a R-S700 and it is pretty solid!
I also like that it has a sleep timer function.
It has pre-amp outputs and main amp inputs should you ever decide to use it with a different amp or pre down the road.
It also will automatically go into standby mode after a period of no input (4 hours, IIRC, but I think I set that, you may have options). I believe it automatically powers up when it receives a signal, but check me on that if it matters to you. (It matters to me because I may eventually hook it up to an Amazon Echo Dot and use it for my alarm clock).
It does not have any digital inputs, so you might stick with the A-S301 if that is critical to you!
Here is a link to Yamaha Stereo receivers at A4L. It is easier to navigate, compare specifications, and see images than using Amazon IMHO!
https://www.accessories4less.com/make-a-store/category/stereoreceivers/home-audio/receivers-amps/stereo-receivers/1.html?brand_f[]=YAMAHA
I also have an A-S700 which is a very strong amp, but I like the flexibility (and the layout of the RC) for the receiver better than the one for the Integrated Amp!
Hope this helps!
