Anyone here got experience with the Chinese RISC-V chips?

I've been thinking about acquiring one of these for a while, because RISC-V sounds quite interesting, but I think I should ask about it here before I spend money on this stuff and the shipping...

First of all, how well does it run Linux? It appears that MangoPi uses their own distro, so I could imagine that a standard one wouldn't run... I don't know about the Sipeed chips. Did anyone here try?

Secondly, which specific model do you have? It's a little hard to get an overview of what's currently available (MangoPi and Sipeed are the only two that I know), I would appreciate a list or just the name of the one you have.

And, in general, what's it like? Does the shipping take long? What are you using it for?