Both heads can be ordered with or without quick release clamps (either knob or lever release).
The Markins lever release clamp can be adjusted to fit the slight differences in camera plate/L-bracket widths, the RRS lever release is designed to work with RRS and Wimberly plates, but I've heard that most Kirk plates work well. A knob adjusted clamp will work with any plate, any time.
Even if you go with the adjustable Markins lever release clamp, it makes sense to stick with one brand of plates as making adjustments in the field takes time and isn't really fun.
I already had a RRS lever release clamp and RRS L-bracket plates so I bought my Markins M10 without a clamp (I like the handling on the Markins better than the RRS 40). A little loctite made for a strong fit and all works perfectly.
My recommendation is to pick your preferred head and clamp, and stick with one brand of plate - just keeps it all simpler.