Just my opinion but...
Over the last ten years I've had almost every combination of transom wheel types/makes on different SIBs... from home made to £250 Zodiac ones.
We often trundle the SIB a fair way down the road, over kerbs and down unmade slipways so strength is very important. I have seen photos of budget wheel legs snapping off and leaving a very sharp end threatening tube damage.
What I have now is what I think is the best. They are the Trem type that are rated to 180kg (as opposed to the similar looking Trem ones rated to 100kg). They cost about £140-150 a set and are the type Honda are happy to sell with their own label on.
Their folding mechanism locks into place up and down better than many and there are no pins to insert (just a pair of pins to remove if you take them right off). Importantly they have the extra support "button" low on the transom which a lug engages into giving them great strength (hence the increased weight capacity).
Finally when you pack the boat away they leave a very small bracket which I just place a small piece of sponge over to totally ensure there could be no damage to the tube material.
They are these here... http://www.rib.net/forum/attachment....9&d=1428739114