What is your opinion on their relative merits and faults?
In my opinion, sombo guys have better takedowns and are more well rounded, but not as good as BJJ guys in matwork.
BJJ guys are spectacular at groundfighting, but in all the schools i've visited, not many work on takedowns in a significant way.
I'm not talking style vs style. I am saying, who has the better training methods, and which one do you prefer? And which one is better for MMA?