I used it back in the Windows for Workgroups, and it was pretty super lame. Jammer was way ahead, and I still use it every once in a while, but usually only for stupid things.
Band in a box is the same as painting by numbers and guitar tab, or steinberg's virtual guitar. They produce a nice end result but are kind of blunt tools. Band in a box produces nice sounding tracks as long as they fit the formula. I actually didn't know it could be used as a recorder? What you are comfy with I guess? I certainly tend to use software I am comfy with before other stuff I'm less competent with = so who cares what others think if it does the trick!
I tried it many years ago for basic backing tracks, but never actually recorded songs with it. Once I got EZDrummer, I never went back to BIAB. Last I looked, it's pretty expensive.
And I know professional musicians who use it....in fact as I understand it, some well-known pros have provided licks/etc which it varies off of. IMO could be ideal for some backing/rhythm instrumentation.