Gillette silver blues are a excellent blade,as are most of the russian blades,.. nothing wrong with Derby Extra's..as you stated a very forgiving blade, used in an aggressive razor they are a great match i use them once and bin them,..i actually like using them,they are in IMHO matched up with a non-aggressive razor are wonderful blade to learn your technique, get your confidence, and most of all learning you to enjoy the DE shaving experience..i'm still learning my technique and they have guided me into the world of DE wet shaving...they have a mixture good/bad reputation though,probably through shaving snobbish biased reviewed opinions. Regards.