Very tightly strung synthetics.
I strung up one of my extremes tonight before I went to go play with a technifiber 17 gauge synthetic in the mains @ 68 pounds and gosen OG sheep 16 in the crosses @ 65 pounds. I must say I liked the feel, cant speak for durability as I only used it for 6 games. It gave be a very responsive crisp feel that Ive never had before with any other poly syn hybrid or all sythetic or all poly. This is the tightest I have ever gone in a racket.
What string could I try and string tight as a MF and get that same crisp feel? Im thinking something like a multifilament, I dont really want to use gut, because its too expensive.