I just bought a Kata E-702, and would be interested in comments from some of you who've used it successfully.
The attachment around the lens is a soft sleeve with drawstring, and around that is the velcro tube. The main problem appears to be the drawstring. Unless the lens has about an inch of tube that's always exposed over any zoom length, there isn't anywhere for this to securely wrap around without interfereing with the lens movement (a Canon 17-85 zoom in my case). It also must wrap in such a way that rain doesn't seep past and run along the underside of the lens barrel. Hence the need for some kind of ridge to both prevent the drawstrung sleeve from slipping off and blocking water seepage.
The velcro tube is what it is, but on a short length zoom it either gets in the way of holding the zoom ring or slides forward and comes into view through the lens. I may remove this part, looks like it's really only needed to attach lens extensions.
Overall the Kata looks like one of more useable solutions due to it's clear bag and easy hand access to the camera but needs a bit of improvement. I think I'd like to glue the lens sleeve to the ring of a screw-in lens hood, which would then screw into the UV filter. In this way, the front end would be completely sealed and reliably attached.