Only similarity is the baseplate. They ride completely different.
I agree that the durability of the highback is a question mark, but I was assured by B that it was really strong. Mine should arrive next week so we'll see when I start riding them.
If your prophecy are still fine just keep riding them. You're only losing out on the genesis highback really, if you can call it losing out.
Or, sell the prophecy now, while everybody still remember them