I have yet to play a set of DR strings that I like. I use Ric (nickle rounds) on my 4003, and also like Fender, EB Slinky's, and Roto's, (nickle rounds), and for flats, The Roto 77 Jazz flats make me pretty happy. My 4004Cii is strung BEAD, and I just put a set of Fender nickle rounds, 65-85-105-125. Absolutely perfect.