There hasn't been a wrestler who has sucessfully controlled Machida with the notable exception of Jon Jones who has wrecked everybody. Even then, Machida got back up. The distance of his stance and his speed and pedalling are too muchfor most wrestlers to make a shot and be succesful at completing it.
Machida is a beast in the clinch as well. I love how the haters and Hendo lovers erase how easily he was able to trip Hendo who was allegedly supposed to grind Machida out with his superior wrestling. Machida has pretty awesome TDD and his own bag of trips to dish out
Sonnen, though an awesome wrestler and a middleweight(?) isn't on the outset a likely candidate to wrestle win Machida. If Silva was able to stuff Sonnen, as soon as he decided to actually distance himself properly, Machida shouldn't have many problems either. Also, Machida has pretty great defensive jits and get up ability.
This is before we talk about the striking disparity.
Jones however, beats Machida again I am fairly sure. There's nothing new in Machida's game that tells me he'll be able to dethrone Jones. Which is cool, cause them he and Anderson can switch divisions.