I have used mine for about three years now, and I am really happy with it.
I use it as a dual channel switchable pre-amp for one bass: channel B with extra mids (freq at 800, middle at 3 o'clock) and channel A for a scooped slaptone: bass and treble boosted and enhance filter on.
The drive knob has a huge impact on the volume of channel B, but as long as I don't use it as a real distortion (which I don't like the tone of anyway on the microbass), the boost knob of channel A is sufficiënt for getting unity gain easily.
I just add some mild drive (drive at about 9:00) and I get unity gain with the boost at about 10:30. I feel balancing both channels is only difficult if you turn the drive up. So not having any use for the overdrive would actually be a good thing!

You can also close the drive completely if you like and still have the channel functioning perfectly.
The microbass works great great for home practice: I put my pedalboard anywhere, plug in my ipod (in the FX-return) and headphones, and I can practice with full pedalboard without bothering anyone or having to hook up an amp.
I didn't experience the hiss problem mentioned above at all, my unit is very silent. I never tried the effects loop (only FX-return for plugging in Ipod, and FX-mix to blend Ipod signal with the bass, which work great), as I run all effects in front of it.
The only thing I that would make it even greater would be to have all eq-controls on both channels instead of only parametric mids (although the freq starts at 50h) on B and bass and treble on A. Of course, you can use all by A+B-ing the channels, but then you lose the two-channel aspect...
Anyway, for my use at the moment, the eq certainly suffices.
All in all a great box that I would recommend!