If you'd like alternatives to look at, wikipedia has a Comparison of Revision Control Software, with lists of GUIs for 'em (if you link to the details on the software -- in the list, it just mentions platforms / frameworks used)

I'm guessing there's probably other comparisons out there with more detail -- each of the individual product's pages, or their official sites would probably explain why they think they're better than the others in their field, if you wanted to see which would best fit your needs