I like Tszyu here, but it could easily turn into a Vince Phillips affair. If Tszyu can't hit hard enough to get Randall's respect he's done for because Randall has much better stamina and can hit well himself. That said, Rosario and Pendleton (two big right hand hitters) did trouble Randall, and if Tszyu can nail him flush it should be enough to keep Randall a little cautious - enough for the pace to come down to Tszyu's liking. I'm not confident in this prediction though...
The Rosario and Pendleton fights were a bit early in his career just as he was getting serious. The Randall that fought Chavez would outbox Tzsyu in a tough contest.