had all of the above and most recently F1GSD3s not to be confused with the rubbish early F1s, after having most in the same size on the same car i can honesly say they are all very good but just got thier own little charectistics, there is so little to choose i would buy the cheapest out of RE720, SO2, SO3, P zero Assims F1GSD3s
RE720s will almost certainly be the cheapest by a few quid but they just lack image for me (despite being good and lasting OK) so spent a few more of my hard earned on the GSD3s I paid £170 for 4 but that was a bit of a deal. expect to pay around £50 each fitted for the above