No, Grimes isn't better than Cro. He could be this year but based on where they are at this moment Cro is better.
I never liked Vontae that much. He had a solid rookie year with us, then he fell off the map in inconsistency. Sean Smith didn't help matters either ... him and his 1,000 dropped INTs.
Revis was always better than Vontae, anyone can see that. In regards to Grimes and Cro, lets give Grimes more credit than he deserves. The guy was a Pro-Bowl caliber CB before he tore his Achilles, and this coming season for him ... its a "prove-I-still-got-it" season for him. Cro I think has the edge as of now, but not by much.