I'm a long-time 6.1 user. 4.0 player knocking on the 4.5 door (just to add a little qualification to my opinion). By no means a world-class player, but decent enough to offer my opinion on the frame.
To an extent, I agree with Fuji about using poly, as everything else makes a 6.1 into a rocket launcher. I used synthetic gut for the longest time, but strung it at 65. I felt that I had to go up to that tension because I'm a big hitter.
For a while I used Volkl Cyclone and really enjoyed the response. Big Hitter Silver Rough was nice as well. I hit for a little while with a full bed of Big Banger, but I never felt Luxilon was worth the price.
In short, go with a cheaper poly. I strung mine at 55 and really enjoyed it.
Looking for Sarasota-Bradenton hitting partners (4.0+). Message me through my profile. Get in where you fit in.