The Emotiva Gen 3 uses a switching power supply that does not have a whole lot of capacitance. The power supply has 4 x 6800uf caps, but it's a dual rail power supply, so you are really only going to be using 2 x 6800uf (the idea is that the switching power supply recharges the caps so fast that you don't need big ones). It works somewhat, but this amp has bass that isn't that strong or thick. Bass seems thin and hollow sounding. The amp does have fast response in the high frequencies, but limited because of the lower cost components.
The Arcam is going to sound a lot smoother and refined, but it has that Class A type of sound where it is very smoothed over - almost to the point of sounding just a tiny bit artificial (like many other high bias Class A amps). It's a personal preference. The Arcam will likely have much better bass because of the linear power supply.
The Emotiva will likely have a more neutral sound with better high frequency detail and response, but it comes with other compromises.