your missing some pockets on the G4
mine has: hand warmer pockets, 2 large front pockets each of them having 2 smaller zipper pockets on the front (total of 6 front pockets), large pocket in back of jacket, and if i remember right there is 1 or 2 inside pockets also
Simms website retails these at $479.99 which is better than mine which was $599.95 !! I do NOT like the new colouring though(mine is dark grey/orange), what were they thinking using a yellowish colour
G3 jackets is basically the same but has 2 less small pockets upfront is the only difference i see
Love my G4 because there is no need for a fishing vest when im fly fishing even though i do wear a waist pack because i dont really like having my pockets jammed full and bulky infront of me.