I'm sure he beat Funaki in 2007 but one bout (especially out of each other's primes) is hardly anything to go on. Still, I'm a massive fan of Saku's PRIDE work but I won't deny the capabilities of each. I wish I had a time machine and booking capabilities, now.
Sakuraba in his prime was light years ahead of Funaki. Funaki's striking game was vastly superior but Sakuraba's ankle pick is stuff of legend. Sakuraba also took out the Gracie's and would have most likely beat the shit out of Rickson. Something Funaki couldn't do. Luckily for Rickson, he always had more excuses.
Katsuyori Shibata has had MMA fights too. The most knowledgeable though might be Minoru Suzuki.
This Is Sum Bull Man. I Knew This Match Was Gonna Happen Because On Raw When The Sheild Beat Team Hell No At The End Of The Match They Held The Tag Titles And They Did The Same To Kofi. Kane And Brian Better Win Or Its Gonna Be To Scripted