You can also use Seal-Lines as simple pegs in a rudderless boat, as I did in my Arctic Tern 17. Pygmy traded/upgraded me from Keepers (ironic, isn't it?) for about $20, I think.

The reason I did this is because in my tupperboat I could never settle on a footpeg position, and I'd get frustrated squirming around trying to reach the toe-release button to adjust them.

The Seal-Lines definitely solve that problem, and they're comfy and solid. But they're costlier, heavier, the tracks are bulkier in the bilge, they don't lend themselves as easily to mounting without a drill-through, and of course since they adjust by hand you have to pop your skirt to do so.

And, I've found that with a custom carved seat and thigh braces, I never need to adjust my pegs -- at least not until I become willing to let someone else paddle my boat! So, I'm still unresolved as to whether my Keepers actually were.