I've been using the Gary Willis signature set from GHS custom shop (with a 030 progressives string on top) , but the stores in my area here in Norway can't seem to keep'em in stock. So I've decided to change to another brand that they seem to always have in stock. The brand I'm thinking of is Rotosound RS666LD. The GHS's are an alloy , 98% stainless steel and 2% nickel roundwounds gauged: 30-45-65-85-105-135 , while the Rotosounds are stainless steel roundwounds gauged: 30-45-65-80-105-130. Will the difference be big concerning playability and sound?