[Chicken Scheme](
https://call-cc.org) is fast, makes native binaries, and has a giant library of "eggs" covering most of the SRFIs. It's R5RS working its way towards R7RS. I've been using it for my "Python but fast" code for the last year or so, and it's one of the best production languages I've ever had.
[Chez Scheme](https://scheme.com) is super fast, and has the best REPL I've ever seen, but can't easily make binaries, and has limited external libraries. It's R6RS, which I prefer, but in the event you find other Schemers to work with about half of them are going to be annoyed it's not R7RS.
I found Racket to be substantially slower to compile and at runtime, the library is weird and not what I expect of a Scheme, and DrRacket IDE has some annoying quirks (it destroys your REPL environment every time you edit & run source, which is just monstrous). It's really heavily designed around educational uses, not so much production, and with the "Racket 2" changes it's likely to fragment and chase off any serious users.
Learning one Scheme (with SICP, TSPL, etc.) gets you 95% of the way with any Scheme; not so much with the three major LISPs (CLISP, Clojure, Arc). You'll still spend half your time reading library docs and SRFIs, which is where they all differ.
With any Scheme or LISP, you're going to face opposition from soi-disant "programmers" who don't like to learn anything about programming, and managers who don't want to support anything that isn't in the last 5 buzzwords they've heard, but if you own your own project, it's pretty great.