Personaly i found abcl a bad experience.
Thoughts on ecl & clisp ?
sbcl works nice & fine. But i’t’s the only lisp implementation i know.
There are good books on racket-scheme & chez-cheme.
The only book i know for lisp is, “Common lisp , a gentle introduction to symbolic computing”.
I know in general there are thing in Serapeum that don’t work properly in ABCL, but I have gotten gotten patches from ABCL users so to be fair there are definitely people using it there.