I have had both. They're all similar in fit and finish. They hold up well in a lot of weather. I had both on my Bronco through several PA winters and they did an awesome job.
That said, I am currently running a Bestop Supertop, and the reason is that I like to have the wiper motor in the stock location with the cover and visors. The Rampage/STC/Kayline design requires the motor to be lowered with a bracket, and the stock cover won't work with it. I think one of the vendors has a cover for the lowered motor, but from what I can tell it looks like it does not work with the visors.
The Rampage design does allow the top to be removed more quickly too, so if you're all about taking the top down and up then the Rampage top is the way to go.
The Rampage top also has a wider array of materials and colors. The Bestop is only offered in Black anymore.
Good luck
Rich