My race vehicles all use Tekin motors and ESC's with Spekrum radio and servo. They match mostly because when I got back into the hobby, I wasn't sure about mixing and matching either. But in my Wriath I have Castle ESC, Hi-tec servo, Tekin motor, and Spekrum radio.
All seem to be working very well.
I've always used different brand batteries but have been using SMC exclusively for about a year with no issues.