I've signed up a long time ago (yay early adopters I guess), so I can't comment on the sign up process or setup with your own GPG key nowdays.

But their website works 100% and provides all the functionality if you don't let them host the private key (they give you an easy-to-inspect snippet to paste into your terminal that downloads/signs/uploads things for them. Note, it does do anything when you paste - you need to manually hit enter)

Not disagreeing with you - Just adding my 2c.