I've been shooting Rugers for about five years now. Picked up a Mk iii Target just after I began target shooting after an almost 60 year absence. Then picked up a BuckMark Micro Target. Later, I bought another BuckMark, can't remember which model. Decided I liked Ruger better. Now own a Mkiii Competition Target, the Mkiii Target, a Mkii Government Target and a Mkiii TALO Hunter which have all been modified with Volquartsen Accurizing Kits. Those kits made all the difference. I've always found the Rugers to be easier to disassemble and reassemble than the BuckMarks. Also found the Rugers to be more accurate. But, that's me, a personal thing. I suggest getting the one that appeals to you, practice and if necessary (in your own mind) modify it. I shot the Mkiii Competition Target last week. At 25 yards, using a sandbag and a Simmons scope, the groups were mostly one inch. Found I'm getting shaky so I'm going to readjust to 15 yards. Probably won't help much, can't hurt. I do shoot slightly smaller groups at 15 yards using red dots.
An aside, I own a couple of S&W Models 41. They are more accurate than the Rugers, at any range. Also have a Hammerli Xesse Sport which is even more accurate. Also picked up a couple of S&W Models 422 to use for plinking. Nice little pistols, about as accurate as the Rugers. They're all easier to service than the Rugers. However, they all more expensive than the modified Rugers, except the used S&W Models 422; they were less expensive than the stock Rugers.
Again, my advice is buy what appeals to you, practice and if you feel it necessary modify to get what you want. Basically any of the models you're considering will get the job done.