Having pre-ordered or crowdfunded a bunch of exciting tech products, I’m pretty shy about that now. I’ve had a lot of stuff underdeliver (i.e., not really work), deliver years late (after the tech is cheaper and commonly available in all competitors’ products), never deliver, be available much cheaper immediately after delivering, become useless when the company goes under two years later, etc.
In one spectacular fail, one company sold me based on video footage of prototypes that turned out to have been entirely faked. They threw up their hands and, walked away after spending everyone’s money.
Most were from companies or individuals with proven track records related to the things they were trying to build. Most were “all finished except for final manufacturing.”
If production units of your ground-breaking product aren’t in the hands of unbiased, independent reviewers, it’s fiction to me.
I can think of one thing like that I preordered that worked out well and, even that was delivered much later than the original estimate.