I too settled on SBCL for a while, but then looked around a bit wider. Clojure is an intriguing development. I recommend that you look at it, both the language and the community. It has a good promise, borrowing the best from the older lisps and leaving behind the unnecessary legacy.
So, unless you need to support or interact with past Lisp code, I think Clojure may be a better tool for most of us. YMMV, as usual.
Emacs coupled with SLIME provides the best development environment I have yet experienced. For me, the greatest downside is that the code I end up with is often quite system-specific.