I searched these forums, but I didn't find any talk about ZVOX, so I figured I'd throw in my 2 cents.
We have a 32" Samsung in the Living Room (bigger toys are in the basement ). We found the speakers on the samsung were pretty weak when we were trying to watch a flick or a concert DVD, etc. So... we picked up a ZVOX Z-Base VT420 about a week ago.
We were looking at the ZBase 420, and then noticed their "special edition" model: the VT420. Basically, it's the same guts as their ZBase 555 minus the surround effects. etc. The bonus was that the VT420 was the same price as the 420. SCORE!!
So, we've had it a week, and I must say it is a powerful amp/sound bar. Installation and setup was dead simple. There are no voice sync issues. The sound is great. Even cranked up, I notice no distortion. I cranked it as high as my wife would allow me (i.e. "the look"), and i noticed no distortion or crackling.
As far as the bass is concerned, it has plenty of punch. So far we have watched mostly TV, and a Live Concert BluRay. They all sound great. I haven't had a chance to throw an action movie at it yet... so I'll report back when I have the chance.
For anyone on the fence out there on a base style soundbar.. these live up to all the great reviews you've read about online.