The ones I've played, generally speaking, have been really nice instruments.  I used a 3.5 octave instrument at a clinic last April, and except for the low C, the extended range was outstanding.  (The low C wasn't bad, but I had to be a little careful where I struck the bar, to avoid some overly-pronounced overtones.)

Generally, I like Musser bars slightly better than Yamaha bars, but I like Yamaha frames better.

If money is an issue (it is for just about all of us, I suppose), have you looked into Ross instruments?  I've heard some very good things about their vibraphones, and the Ross marimbas I've played have been quite good. (I haven't played a Ross vibe yet, so I can't comment on it.)