Trektops are the same way. Operates on the roll cage without the cage. I bought one and I'm totally diggin it. ...i really should write that review... Anyways, I've only been witness to 2 drawbacks on the Trektop: if windows are down on the highway, the top will hit the wind pretty hard ... like a huge subwoofer on your roof. That and I can stick my hand out the jeep with doors closed windows up. BUT, i haven't had any leakage so i don't care about that really.. until it becomes winter and I've got this constant freezing wind on my bald head. The Trektop comes with the door surrounds when you buy it from 4wd.com. The install isn't too technical, just don't put the bar mounts on upside down and assume you have it correct and the factory gave your crap mounts, so you get your hammer and shape it to make it work, THEN head back to the instructions and notice that you're an idiot.
But a quick pros/cons for framed vs. no frame:
framed pros: better seal. more "structural integrity" (e.g. the cloth isn't moving unless you want it to move or it's broken) storage.
no framed pros: 1 zipper, 2 pieces of cloth, quick removal/detachment, metal door surrounds. (personal opinion) cooler cosmetics/look, cheaper to completely replace
framed cons: security, lots o zippers, lots o pieces, complete replace cost high,
no framed cons: security, floppy feel, rear veiw mirror partial blockage, no frame which means no real place to store it if you take it off away from home.
Thats what I can think of off the top of my head. I had a really crappy framed top with the jeep for a long time, and getting this trektop made me ubber happy with the upgrade.