You'll really like it, unfortunately they can become addictive.
Bottom to top: 1985 686 no dash, no M, 1990 617 no dash, 1985 586 no dash -M.
The 686 has the best trigger I have ever shot on a revolver, smooth as glass 8lb 0 oz in double action,with the 586 not very far behind and the 617 not...