I've decided to back them, even though they may be a bit small.
The heights quoted seem to be overall figure height. Most are around 22mm, while the wizards are 28mm, presumably because of the hats.
These are pretty much the same height as some Ral Partha dwarfs I backed in another KS a few years ago. They are lovely figures, but almost too small to use alongside even old school GW figs.
At best the Midlam ones will work with old school GW and Reaper, at worst they should work with Ral Partha. Either way, they should prove useful