The Sti2 has mpf of 701+ (not sure why the +) while the TS3 is 849 and the TS1 IM is 728. I currently have the Sti2 and was thinking of upgrading but am sorta confused now

Britt Lindsey Answered question October 2, 2023

DO consider KE4 max. After making both Ts-1 and Ts-3 sets, still was
unhappy. Made KE4max sets and love them.
Used Steelfiber 70 A shafts, but we all know THATS a personal
preference