SBCL: is it as good as Allegro? I haven't seen an IDE as beautiful and comfortable to work with as Allegro (although I'm barely a Lisp hacker, just a fan).
I don't know what metrics you'd use to decide it's "better". Certainly the native code generation on SBCL is pretty darn good.
I think Allegro has better tools and libraries, but SBCL is certainly suitable for professional work. At this point we're talking about matters of degrees.
