I *think* the new Hi10 keyboard doesn’t fit the Vi10 Ultimate, not sure where I read it though. But I could be wrong.
I pre-ordered the Vi10 Ultimate (hopefully, it’ll ship soon…) because I didn’t want to spend more money on a more expensive Hi10 and thought the Vi10 would ship sooner (which it didn’t, so at the moment it probably doesn’t matter anymore). If cost isn’t a problem for you, just go for the Hi10. More memory and a better screen.
Maybe wait for the 11/11 AliExpress deals to get a good deal?