If you have a Belgium Browning, and have a set of Medalist or International Medalist grips, and also a set of Challenger grips, I "challenge" you to shoot some groups with both grips back to back. See how they compare. The purpose, IMO, of the Medalist grips is NOT to feel good. It's to shoot good. As I mentioned above, whichever of my guns have the IM grips is the one I shoot the best groups with.
You can get a feel for the concept by just holding your hand out with an "imaginary"gun in it. First, shape your hand if you're gripping a pistol with your fingers curved back towards the heel of your hand. Feel the tension in your hand and forearm?
Then relax your hand half-way to the flat position, kind of like you are starting to extend it to shake someone else's hand. Your fingers are about half-way between closed and opened straight out, and are in a relaxed position. That's approximately how your hand will be when you grip the Medalist grips. Notice how relaxed your hand and forearm are compared to when you're "gripping" the gun with closed fingers. That's the difference I feel when holding the actual guns. I love the IM grips.
Your first impression will likely be that the Medalist grips are huge and that you barely have the gun securely in hand. But there's a reason for that, and it's because your hand is much more relaxed that way. I have some targets around here someplace where I did the shooting tests and the improvement in accuracy is clear for me. Perhaps it'd be different for others, but I think it'd be the same for a lot of people.
Here's a photo of the IM grips in hand. Notice how open my hand is.
Here's a 1911 in the same hand. Perhaps it's just my imagination since I also know how the two guns feel in my hand, but I can "see" the difference in muscle tension.

(Of course you are going to have to grip a .45 ACP tighter than a .22 LR of similar weight.)
I also have a set of Medalist or IM grips that have been modified and contoured to fit someone's hand (I think they came from Germany). They also fit my hand pretty well, but I think they negate some of the purpose of the original grip design because they've been trimmed down to allow a more closed hand on the grip. Here they are on the gun on the right (I refinished the grips after I got them).