If you have a 410UL, I would stay away from the DB750. The huge low end of that amp, and minimal EQ control (especially in the mids) does NOT line up well with the deep low end and relatively polite mids of the 410UL. This is well documented.
The 902 also doesn't make much sense with a single cab, since it is a non-bridgable dual power amp design. If you like the Epifani voicing (creamy, fat and a little on the dark side) and have a single 410UL (4ohm), the Epi502 will drive the 410UL to full volume in a smaller, lighter, much less expensive package.
If you don't need HUGE volume, the new Puma500 is a beautiful, fat, smooth, warm sounding head with a 4ohm 410UL that has much of the Epifani amps creamy, fat low end, but MUCH better control of the mids, and a more prominent top end (if you want it... it's easily dialed back with the 'taste' overall voicing knob). It doesn't quite have the balls and volume of the 502, but is 1/3 the size and weight, and a few hundred bucks less. It gets PLENTY loud for most applications though.
IMO and IME.