Are kickup Turbo Fins worth it?

I ordered and received my kickup turbo fins for my two iTrek boards. However, they seemed small and when I compared them to the regular fins on the board, I found that the turbo fins are only about 1.5" longer than the standard. Has anyone tried them and do they make a worthwhile difference?

I went home and compared the "turbo" fins to the regular ones I have. The supposed turbo are only slightly bigger (same width and not even 2" longer). I can't see how that's going to make much difference. I didn't test it in the water because I didn't want to get them wet and loose the ability to return them. Returned they are!

I need to compare the size of the standard vs turbo fins on my Island kayak - hopefully this weekend if the weather cooperates - as the difference was much more noticeable both visually and in the amount of power they provide.

If Hobie has any actual information on the power difference between the iTrek standard and turbo fins, I'd be quite interested. Spending $200+ per set of fins for not even 2" of difference just doesn't seem worth it.