If by performance you're meaning higher velocity then as I've mentioned before that search is a wasted one. Velocity really isn't that important once it goes over about 1000-1100 fps using cast bullets. The REAL advantage of those longer barrels and the reason I love them is they get that front sight far enough away from my eyes for it to come into focus which it doesn't on short barrel guns.
Of those currently made I think Taurus still makes a 12" Model 44, I had two. Why two? Cuz the first was such a POS they replaced it free of charge. Guess what? The second wasn't a lot better. I returned it to the dealer where I'd bought it and told him I wanted no more Taurus guns. I used to have a S&W Model 29 with 10-5/8" barrel and an adjustable front sight that had four different height settings for use in sillouethe shooting. Man I loved that gun and sure wish I'd not let go of it. I've never shot an iron sighted gun that worked better.
If you're like me and need reading glasses and plan to use iron sights get the longest barrel you can. If you're gonna scope it then a 6" is adequate and a 7.5" to 8-3/8" is more than enough.
