I’m with Peter, I took the backbands out of my kayaks a year ago. It allows more freedom of movement for surfing and rockplay, and it allows more rotation for the forward stroke…
Looking at the two…
…photos here: http://www.seakayakingusa.com/gear.htm
One looks to slope back while the other is more vertical. What’s the plan there? How wide are they? I have some minicell in the garage. I think I’ll make one.
I have just the bottom…
…in both my Terns and love it. It gives much better control (no sliding around) and raises the CG letting you edge the boat much easier than with the pad.
A friend that got the complete seat thought he would have been better off just getting the seat and adding a backband.
I you want to do layback rolls, the backrest part of the seat is to high and ridgid, but the sea itself is very comfy.