The 7900 is made by ATI and they have been the OEM for amps offered by a number of companies including Outlaw. ATI has a solid reputation. Is the 7220 built by ATI? If so, I don't think you'd go wrong with either. The real questions are: What kind of speakers will be driven by the amp and how much headroom is desired. FYI, a Class D amp can achieve the same power without literally hurting your back and uses less energy than the typical Class A/B. ATI makes a couple of them.