1) Sky revoked the licences, there was a BBC article. They can't use the Sinclair or ZX Spectrum names at all any more as of a few days ago.
2) Even if it was amazing, their attitude to customers stinks. There are people on their 4-5 HUNDREDTH request for a refund, unanswered for years.
3) There's almost no way to sensibly add games easily to the SD card. It's missing the 1000's of games promised, because they can't secure rights.
4) The firmware is apparently (according to Lee Fogarty who worked for them) an old one, that was a revamp of one he had tested, and works WORSE than the one he tested. The company doing it didn't get paid so they never finished or progress and there's a huge bug list available that shows what bugs it has. Lots, is the answer.
5) These people have gone totally silent, but the various blogs publishing information from backers and insiders haven't. There's an awful lot of nonsense and politics that's pretty uninteresting and petty but there are some major issues over finance, dealing with people, lawyers and suppliers being unpaid, etc. etc.
6) IndieGoGo are doing nothing. Despite promises. There's literally nothing happening on either of their "deadlines", even after promising action "despite products shipping now". Steer clear of IndieGoGo as they are basically complicit at this point.
I never invested. I'm damn glad I didn't. You can pick up a second-hand GP2X for £50, and that can run all kinds of stuff (generations newer than the ZX Spectrum) and also run FUSE. It looks and works the same, pretty much. It's also 10+ years old, runs standard Linux on an ARM processor and runs off AA batteries and takes SD cards.
That these guys couldn't do the equivalent of stick a RPi in a case with buttons and load FUSE properly over the course of several years tells you quite what the quality of these products and people is.