I have never like scupper hole trolleys (this feeling goes way back, and has nothing to do with Hobie). It just seems to me it is clearly a week area of ANY sit on top kayak.
I have to disagree. The scuppers are actually the strongest part of the hull- IMHO
A tube that connects the top and bottom of the hull strengthens it. I know it's a commonly held belief that scuppers are weak, but my experience, wheeling kayaks well over 1000km in the last 4 years has shown otherwise. If I had been using an under hull cart I'm sure it would have rubbed a hole in the hull or caused other damage as it slipped around.
I know there have been some well publicised incidents where the cart has punctured the tubes but I reckon these can be attributed to either operator error or a roto molding problem leaving thin or weakened walls in the tubes.
A properly maintained cart with no sharp edges on the uprights, that is inserted correctly (no crossloading of the tube) and with the uprights extending all the way through the hull should be problem free. With correctly adjusted cart bushings, the keeper pin and most importantly Roadrunner's tennis ball mod (cushions the base of the scupper) you should have no problems using a scupper cart!