I'm a ShareRoller backer (friction drive for bikes) and it's been 3 years + for that as well. Just recently we were asked to pick our accessories so it's clearly coming in the next month or so (finally). The delay is because the developer kept improving and tweaking and responding to issues caused by the improvements and tweaking and then improving and tweaking some more, a constant cycle. I think that some of the developers are crazy perfectionists (and wouldn't you want someone like that to develop something you buy?) and they constantly see what could be instead of what can be now. And with no administrative structure to rein them in, they continue to "develop" their product well past the time when it could be released. They are idea people, with engineering skills perhaps, but the same qualities that let them envision a cool product also make them less likely to "let go" or be great at customer service commmunication, etc. I do believe Helix will materialize, but on the devs schedule, not the backers.