If you aren’t looking to move to Atmos then a MRX-520 would do the justice. I was in a similar situation and was looking at MRX-520 and a 3 or 5 ch. amp. I already have a Rotel 200w/ ch stereo amp for my L/R, so the 3/5 ch amp would replace my stereo amp. Luckily I was able to get brand new MRX-720 for close to the price of 520 and I bought that. So I still have the Rotel amp and 140/ch to drive my other speakers in my 5.1 esp. the center. The power depends on what speakers you are driving. Either way, 520 or 720 are great receivers and much better than my old Marantz SR5009. The ARC Genesis is simple amazing and that alone is worth Anthem. If I had bought the 520 I would’ve bought an used 3 ch amp. either Anthem MCA 325 or Parasound A31.