To my mind, "lifetime" = Ruger.
"Big enough to fight with" = SP101.
Indeed, my recent purchase of a 3.06" SP101 was with my retirement years in mind. I already owned, and still do have, shorter-barreled examples of the same, but they were often backing-up a larger weapon. I always liked the concept of the 3" small-frame, and deeply regretted parting with a 3" S&W Model heavy-barrel that I had let get away from me years go. I would still pick a bigger sixgun if I knew I was going to have to fight, and could not grab a long gun, but the 3" SP101 seems "big enough."
In the true "fill-your-hand" category, I love a GP100. The original, pre-Hogue GP100 factory grip is
absolute perfection for my hands; I doubt a true custom grip maker could beat it. If I knew I had to get onto a fight, involving guns, and could not lay hands on a long gun, THIS is my choice.
I am not stuck on Ruger; I just think, based on reserch on the 'net and in written literature, plus handling many pre-owned sixguns, and owning a few, that an S&W is more likely to need to be rebuilt to stay tight and in time. I own some S&W sixguns, including a 19-5 that I recently purchased, and which I sometimes carry. I shoot a good 4"+ K-frame about as well as a GP100, and find the 19 a bit more packable that the slightly heavier GP100.
I would not want to be without all three of these revolvers, with each perfect for a certain niche.