The sizes range from about 1,5 inches / 4 cm to 3 inches / 9 mm depending on the figure, and prices vary from about $20 to $200 (ouch!) depending on the figure but also which kind of material you want ’em printed from.
I bought four 3D printed marines (from another seller) a couple of years ago, and personally I was very disappointed about the quality. The material I chose was matte and porous, and not at all suited for painting. But this time it looks like you can choose “Frosted Ultra Detail” which looks much better. But much more expensive.
Still, I think they look great. If I didn’t suck as much at painting minis I’d probably go on a shopping spree. Hopefully they’ll come in full color one day.