I have all four guns, sorta. My GP100 is not a MC, which didn't impress me. My SP101 is 357 in 3+". There is the 686-6 and the only 22 being a pair of 617s. All of them but one 617, bought used, required some level of gunsmithing, so it is not so easy for me to recommend something.
They are all good guns at this point, except the SP101 .357 has fallen idle, since it should be .38 Special only, and there are better alternatives (for me anyway). I have another in .327 Federal Magnum, which I adore as a 6 shot instead of the 5 shot 357. The 327 caliber is a great match for that SP101 3+" platform.
I shoot mostly single action, but the trigger job on the 686-6 make it unmistakably the champ for double action. It wasn't special out of the box.
With the investment in getting these guns optimized, I am not likely to part with any except maybe the SP101 357, displaced by a Smith model 60 Pro series. The SP101 has a trigger job and throats adjusted for lead bullets, so I am torn about parting with it.
To try to recommend something, I personally feel that a 686-6 is a better gun than a Ruger Match Champion. Mine has a plugged trigger lock, so the price can be more reasonable than a pre-lock. It's a good shooter.
It might come down to whether you need another 22.
In a GP100, I would recommend holding out for the standard model but in 5". It is a beautifully balanced gun at that length. If really into that "Match" business, then the 4" might be what you'd want.