I've got 5 or 6 dash ones and like them a lot. Some of these guns have only recently been retired from steady use since the mid 80's. In my experience the pre endurance guns will need a tune and tighten somewhere around the 3000 round mark(locking bolt,spring,center pin and end shake adjustment). That is a lot of ammo in today's world, roughly $3000 for american name brand economy loads. The tune up cost was around $125 minus shipping the last time I sent one back to smith. If the gun passes a QC test and seems to be in good shape. I would buy and shoot it without reservation.
If I was looking for a high volume range toy. One that would make weekly trips to the range for load testing and practice. Then a newer gun would probably get the nod, the endurance package effectively doubles the life of the gun.