I came to some of the same conclusions as you folks.
I was pretty excited at the initial announcement. (I've spent 20 years looking for a worthy successor to the Psion 5mx that I still use every day!) But the uncertainty of crowdfunding, the amount of money, and concern over possible links to the Vega+ situation, made me hold off for several months.
But since then, everything I've seen has added to my confidence. Planet have posted relatively frequent updates, demonstrating lots of progress, and seem to have been pretty honest about the spec and timescales. The appearance of working prototypes and, most recently, actual production models, have made it seem more and more likely that they'll deliver.
(Also, although I'm not sure I follow much of the Spectrum Vega+ story properly, it seems like the real culprits had left before Janko became involved, and he's one of those left to carry the can. I'm not sure that excuses everything that's happened since, but it does at least reduce some of the question marks over his name.)
So for me, the expected benefits exceeded the risks several months ago, and I took the plunge.
In the next few weeks I hope my confidence will be validated…