Levan,
Most 9mm/40 S&W/357 Sig guns (ie G19, G23, G32) are the same frame so saying that higher caliber guns are bulkier is a false statement in most cases. You do lose 2-3 rounds of capacity going to a 40 S&W/357 Sig but you have a more potent caliber even though a 9mm w/ proper ammunition is very effective. It is only when stepping up to a 45 Auto/10mm/38 Super that you generally have to deal with a bulkier gun.
Most 9mm/40 S&W/357 Sig guns (ie G19, G23, G32) are the same frame so saying that higher caliber guns are bulkier is a false statement in most cases. You do lose 2-3 rounds of capacity going to a 40 S&W/357 Sig but you have a more potent caliber even though a 9mm w/ proper ammunition is very effective. It is only when stepping up to a 45 Auto/10mm/38 Super that you generally have to deal with a bulkier gun.