Tech 21 Power Engine
The big drawback of using a regular guitar amplifier with an amp simulator is that regular amps are specifically made to "color" the sound coming out of your guitar. That's what makes guitars sound awesome. But layering the amp sound on top of your amp simulator results in random muddy crap. You have to constantly be compensating for the sound of your amp when designing your patches on the amp simulator.
The Tech 21 PW60 Power Engine however is more faithful -- it puts out what goes into it with minimal coloration. When I switch between headphones and the PW60, the patch sounds are nearly identical (the PW60 has more "air" which seems unavoidable due to physics.)
It'll be a week before I can try it at rehearsal -- which is good because I've got some patch programming to do -- but I can easily get the PW60 up to volumes I'm sure my neighbors can hear without even putting the gain at 50%.
It's slim on features, which I like as opposed to Behringer's habit of throwing shitty digital effects processors in anywhere they can. Three EQ tone controls, gain control, handy XLR in and out and of course 1/4" in. Mine didn't come with an AC power cable but I'm not sure if that's Tech 21's fault or the music store. I have lots around so it was no big deal.
It's lightweight (33 pounds) and nice looking. It's smaller than my Delta Blues 210 so I guess I'm less of a man now.
All in all, I'm very happy with it, five thumbs up.