Many are passionate about the 'no-lock'. I do prefer the cleaner look, like on this 686... but my 617 has a lock and I sure enjoy it too!
If grips matter to you... The no dash has a Square Butt. The switch to Round Butt occurred late in the -4 run. Someone will correct me...
but I believe there are more choices available for Round Butt. Both my 686 & 617 are RB and share my small, but growing, collection.
Howdy Sully, the top grip is a Hogue, below is an Ahrends... both in cocobolo.
While I think the 'no-screw' look of the Hogue looks cleaner, the Ahrends fits my hand a bit better.
And, of course, this is a Crimson Trace. I'm glad both my 686 & 617 are Round Butt so I can switch it back and forth for training.