To me it makes the J frame feeler closer to the K frame. Not really compact for carry but OK for open holster carry and for shooting. Can hit alot more targets than with the orig. wood grips.
A toss-up: 6 of one, half a dozen of the other. Pach grips afford comfort and control, but IMO are too heavy, almost 1/4 the weight of the gun. It's your call; that's why shooting (especially J-frames) is fun!
One other plus is the Diamond Pros are one piece grips while the Compac Customs (on my Night Guards) is a split two-piece grip that doesn't always stay matched/lined up at the joint.
I only use the Diamond Pros for range practice.
On my M360J the Diamond Pros added less than 1oz. to the factory grips weight but are lighter than the Badger grips.
I replaced the Compacts with Diamond Pros on most of my NGs.