In terms of their feel, the MS keys (and e.g. the iPad Keyboard Cover keys) are rather more like the (still IMO wonderful, and pioneering) keys of the Cambridge Computers Z88 (also a Clive Sinclair product). Raised keycaps with a larger volume of air to move the membrane. Quiet and mostly usable at a reasonable pace.

The ZX80/81 membrane keyboard was entirely flat except for the tiniest hint of membrane bubble, with a uniform textured matt finish. Not even textured outlines around the keys. Surprisingly robust; maybe more so than the membrane keyboard of the Atari 400 (which is also a classic of visual design), or, say, that of the BigTrak.