i had one. it's OK. it's not a custom gun, handbuilt or anything particularly fancy. it's basically a GP100 with various worthless changes and a few that are actually useful, such as:
1) chamfered cylinders, which do make loading smoother
2) recessed and nicer muzzle crown - good if you drop your guns
3) slightly better sights from factory, however the front sight dovetail is different from typical GP100 so the usual GP100 aftermarket sights won't fit
4) half underlug, which makes it point nicer although recoil is indeed slightly more noticeable than an equivalent 4" GP100
i found the tapered cylinder to be a pointless upgrade. ultimately i sold my GP100 MC due to the heinous laser etching on the side that reads "MATCH CHAMPION" in bold retard font. sorry it just killed any chance of a revolver-boner. yes i'm aware this is a vain reason to sell a gun but honesty is the first step.
personally if I were in the market for a GP100 i would just get a 4 or 6" stainless model (i personally prefer the 6"), pickup some hammer shims to shim your hammer (otherwise it smacks the frame on each shot), buy a fiberoptic front sight and then shoot the snot out of it. it ends up being the same performance as a match champion without the stupid marketing/signage on the barrel.
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A friend of mine got one.
It compares favorably with my S&W Model 66. Similar size. I think my Smith balances a bit better. Ruger is all monotone brushed stainless. S&W has blacked out controls. Ruger has nice wood grips. S&W has Hogue-like rubber grips which I prefer. Factory trigger on both is very nice.
I just can't get past the MATCH CHAMPION billboard on the side of the barrel of the Ruger. If you like it, buy with confidence. It's a nice gun.
^this is an interesting point in comparing to the model 66. I currently have the new production S&W 66 and if the price is similar to a GP100 MC, that decision is stupid easy which would be to choose the M66 all day long.