I thin its rather simple.
F4 good turner, quite good in climb, topspeed not the best, lightest 109 in AH
G2, not as good in turn as F4, but better climb and speed, weight increased a bit
G6, turning capabiliteis further decreased, climb and speed close to G2 but not exactly matching, weight increased again
G10, fastest and best climbing 109er, turning maybe bit better than G6, but nowwhere near F4,