I have 2 581's, no 681's yet but it's a goal
It truly is everything you need and nothing you don't......no flimsy sights to mash up, beefy construction.......it's a fighting gun made to put .357 slugs on a bad guy in DA at combat ranges of 0-20 yards, not a 25 yard single action Bullseye revolver
The "new" equivalent would be the 619 I would gather.