Hi,
I am.
both xotic rc and bb to my dc-2 and they sound very good.
What I do is keep the gain at 5 on both the clean and lead channel.
On the lead, the BB is great to add some more gain but still keep or increase the dynamics (which I think this channel hasn`t got enough) and i can get a sound which I like.
My dream lead sound would be the one of the lead channel of a lonestar classic...
On the clean/rythm channel instead the BB can give you a lot more options, in fact by keeping the gain at 5 I have a nice clean sound and use the pedal even for rythm parts and not only solos (I boost the cleans with the rc, use only the BB for rythm, and both, with rc into bb, for leads).
I like it a lot.
It`s very transparent and believe me, anyware you set the knobs, it will sound good.
Marco