I use a Muhle R89 tis the best shave ever for me and I use 7oclock sharp blades because they give a nice smooth soft shave
other blades I have used are
Feather- too dam sharpe and I cut myself alot and I suffered razor burn. Not for me
Derby – felt blunt
Merkle – ok nowt special
Wilkingson sword- not very good
please note these are my findings but for othere folk may dissagree but each to there own
Gilette 7oclocks for me good for about 3/4 shaves