I have the 714s and they are great glasses. The folding feature at the bridge and temple are neat but can be a bit annoying when handling / carrying them around indoors.
649s are almost identical with the exclusion of the extra moving parts and taller temple arms. Also I believe the 649s come in a smaller lens size too; 48 or 49mm if I remember correctly (so 3 sizes available vs 2 sizes in the 714s).
649s are almost identical with the exclusion of the extra moving parts and taller temple arms. Also I believe the 649s come in a smaller lens size too; 48 or 49mm if I remember correctly (so 3 sizes available vs 2 sizes in the 714s).













If they're too small, well, you can get them in 54, 56 and 58