I haven't used the MMO7, but if it's half as good at the RAT7/9 then it's still among the 3 best mice ever made. My RAT9 has held up quite well, I wouldn't say I'm hard on it but I'm certainly not a light user. I can highly recommend the RAT7/9 from personal experience, and the MMO7 from brand experience. Those mice are amazing!
ASRock A55 Pro3, AMD A8 x4 3850 @ 4.7 + Xigmatek Gaia, Thermaltake V3 Black Edition, 8GB DDR3/1600, HIS 6870 1GB, 620W PSU, 500GB HDD, 250GB HDD, 3TB HDD, Logitech x530 5.1