At YORCC (and therefore RHR inc dirt), we have made our decision:
http://www.oople.com/forums/showthread.php?t=116998
Obviously, the BRCA provide their own timing gear for all sanctioned events, so I guess it's still "up in the air" regarding the F3's next september.
I "think" the oOple race at RHRD uses YORCC timing gear so unless I'm corrected your MRT's will work there as well (but Purcy's won't).