They are all good revolvers. Some of us like the 6 1/2 inch barrels on blue steel but they all shoot great. The newer guns are more accurate because of the tighter cylinder throats, and stronger so the heavy loads will help to keep the cylinder closed when you shoot it.
They will loosen up in time as the weak link of the N frame is the yoke, as it's the same size as the medium frame guns.
Check the gun out for obvious abuse like broken sights, damaged screws, burrs on the side plate, push off, cylinder open and closing ease. If it is damaged get it for a cheaper price then send it out for repair. Sometimes this is the only way to find "your" gun.
I'm doing that right now on another N frame a 625 that I bought yesterday. The gun looks good, yet someone dropped it on it's head, smashing the sights. Then when you work the action, you need a come-a-long to press the trigger.
I got it cheap so it's going to survive with me, providing smith still has a few parts....
I currently own 2 dash 1s. The 8 3/8 barreled one was sent to S&W because the yoke was undersized. It was rebuilt by S&W when they got it. It was done over very nicely. The other was bought new and has a 6 inch barrel. I wipe it down with a rag when watching TV, but never warmed up to it as my favorite shooter. It's heavy feeling for a N frame, and I prefer the 8 3/8 more for open shooting.
The 2 on the top are -1s