I was in the same dilemma as you! I was stuck between the speedmaster 3861 and the GS sbga413 (cherry blossom). Just my 2 cent, I went with the watch that fit my wrist better, I found that the cherry blossom had a lot slender of a profile and suited my tiny 6.25" wrist. Ultimately really happy with my choice!

I personally love the idea of a watch that could be dressed up or down based on the strap or bracelet. So finding a watch that rides the line between a dress watch and Sport watch would be important for a 1 watch collection imo. To me, a sea master Aqua Terra 150m, could fit the build. On a rubber band wears like a "sport" watch, but on a black leather strap could be worn as a dress watch. 

I personally have been doing this with my sbga413 :)