I'm the author and I'm using Emacs + SLY. Happily switched to Emacs from VIM about 10 years ago when decided to invest all my free time into Common Lisp.
And yes, I have real project experience – a lot of Commmon Lisp libraries at https://github.com/40ants and also I'm developing a hosting for CL library distributions: https://ultralisp.org
And yes, I have real project experience – a lot of Commmon Lisp libraries at https://github.com/40ants and also I'm developing a hosting for CL library distributions: https://ultralisp.org