It's all personal opinion. U can't ask this cause their going to give you a bias answer. I prefer the supertop because I like having the hardware and is easy to take Down and put up. The trek looks better but I like the ease of operation on the supertop
You don't buy a frameless top to completely take off like a normal framed top. A lot of people (including myself) put on a bikini top for 99% of the summer because it's always sunny and hardly rains, so top off and doors off all summer is possible. Yet for those occasional showers I don't have to take the bikini top off then put the full top back on, I just throw the windows on and be done.
Sure having the top completely off is cool, but in practicality I don't like having the hot Colorado sun beating down on me and some shade is nice. The connivence of the frameless top is the fact that when you take the windows off it turns into a bikini top. Although the new NX trektop has the sunrider feature which can give you the more top off feel.
I replaced my old Supertop with a Rampage top and its much faster to take the windows out of the Rampage top and turn it into a bikini top than it was to put down my Supertop. Plus the windows fit nicely inside the top and don't take up any cargo space.
If you are someone who tends to utilize their bikini top a lot than a frameless top is a great option because you get both a bikini top and full sealing top.
I dunno with the recent lack of customer service by Bestop, I really would have to think hard about buying another one of their products. There are a lot of companies out there with great styles in tops.