While I don't have the TGA 5200, I do have a Sunfire Cinema Grand II (225 x 5) amp and a Sunfire Theater Grand II preamp. I've had them going on 10yrs.
Both Sunfire pieces of gear are fantastic. The Sunfire amp has never had an issue, runs cool, and has plenty of rock solid power.
I'm sure that while not the exact identical model Sunfire amp, there's not much difference.