1st - domey like the S-FDs, pretty stiff champ plastic. IIRC these were run for the Russian Open but some were stock stamped. I have only seen these in clear/white and stock stamp.
2nd - Flat and stiff - not dead flat like buzzzes and firebirds get, they have some shoulder, but flat across the top. very HSS. always have a bit of swirl/pearl in one spot on the rim and some blizzard bubbles if you hold 'em up to the light and look for 'em.
3rd - softer, grippy, more translucent jolly launcher blend of champ. not as domey as the 1st runs or S-FDs, not as flat as 2nd. I haven't thrown one yet.