Yes, I've been running SM in SCCA and will next year too.

My suggestion is to use BMW and NTAXS for practice and seat time to prepare you for the SCCA events. My first few years of autocrossing I only ran SCCA and ER events and I wasn't really getting much faster. There's just not enough seat time or opportunities for ride-alongs and coaching (in my opinion) like you can get at an 8-run event with more relaxed rules.