Marantz 2230 vs Marantz 2230B ?

HELP! What's the technical and sonic difference between these two?

The B has two signal meters instead of one, but beyond that there doesn't seem to be any visible difference....
See for yourself at
I like the 2230 better- the (b) model had the whole amp on 1 circuit board if I remember correctly, and seemed a tad less structurally sound. The (b) model also had a plastic escutcheon on the source selector switch which I've seen two go bad after they got bumped- the plastic gets brittle and they'll crack.