For, me currently I'm still a realtive newbie - only played with 4 blades so far (and yes, yes of course there are more sailing to me via the postal service...) Namely Wilkinson Sword, Shark SS, Dorco 300 and the Derby....
Currently, the Shark SS just aren't doing it for me. Biting, cruel and the razor burn was the 2nd worst I've ever had to endure (the Wilkinson Protector cartridge system holds that dubious honour).... dunno, maybe in time as my technique gets honed more (see what I did there? did ya... eh...oh never mind), they will become a good shaving choice.... but not for some time.
When sharks attack, you don't forget in a hurry...
Had similar problem with my first go with the Sharks. I'm not sure if the razor burn came from unknowingly using pressure but once I came back to them with a year of technique under my belt, I found the Sharks gave me the best shave out of all the blades I have tried.