Thanks for the suggestions, i have considered both options but i use my folder as my main bike too. I have used it on long tours, up and down mountains (roads not trails obviously). My daily commute leads me to slopes that peak easily at 50kmh, which is perfectly fine on the 24" wheels...on smaller...fat chance. Also i have already replaced the hinge pins of my Tern once (one sheared during transfer not during riding), so my next bike will definitely not have a weak point inbuilt in the frame. Here you see all of it. I don't see anything better than helix. But I'm still pining on the decision. Expensive, potentially a bit too short, durability of the helical hinges...all combine to make me uncertain.