I was talking about the profile and the differences between the 55 and 66. The link states that they're pretty much the same, just a different size. I never said anything about the type of rubber.
All I know is that around here, just about every Diamond plays the same, as long as they're not all beat to hell and even then they're still about the same except for damaged cloth/slate.
They bank shorter than an average Valley or GC, but they put them to shame in the consistency department.
The best part about rails shortening the angle is that they're already doing half the work for you and you can concentrate more on the hit. I have a problem getting a couple of favorite shots down on them, but damn if they aren't easier on just about every other bank.