I think the Monster motors are some of the most popular stock motors at the moment. Personally, I do fine with P2K and Green Machine.
I would stick with a a car with good local support and the Pro4 and XXX-S both sounds like good choises.
LRP Quantum and Novak GT-7 are some of the hottest. Personally, I'm more fan of LRP, that's because I've had good luck with them so far. My v7.1 is trusty.
Schumacher Mi5 - Sanwa MT-4 / RX-462 / KO Propo PDS-2123 - Nosram 5600 X-treme Saddle Pack - LRP SPX Zero/X12 17,5 - Nosram Stealth Touch Evolution - MAAS SPS 9250