I have a pair of D-Max Sidewinders. These are the predecesor of the Mag Research BFR. Mag Research bought out D-Max and started producing this gun theirselves. I believe they made a few internal changes from the original design, but not sure exactly what changes.
The quality is supposed to be even better than the original D-Max guns.
The quality of the D-Max guns is very good. One of them could have a better finish, but it is a very early gun. The other has very good fit and finish. Both function flawlessly, have good actions and trigger pull.
Accuracy is good. About what you would expect from a Ruger Blackhawk. And that`s basicly what these guns are. Over grown Blackhawks.
One is a standard 6 shot model in .45 Colt/ .410 3" shotshell with 6.5" barrel. The other is a later L5 model (5 shot) in .45/70 with a 7.5" barrel.
Recoil is less than you would expect. It`s heavy in the 45/70, but it`s not sharp recoil like a magnum. More of a hard push.
I do stay with 300gr bullets to keep the recoil down, but there is plenty of room in the cylinder to use 400gr or 500gr bullets if you wanted to.
If you decide to get one, I`d suggest getting one with a 10" barrel assuming you are looking at one of the long cylinder BFRs. The extra barrel length should give quite a bit more velocity from a 45/70 or .444 Marlin. These rounds were not really designed for short barrels.
If looking at a .45/.410 a longer barrel would increase the effective range. The gun has a screw in choke (must be removed to fire .45 Colt) but the shot still spreads pretty fast with a 6.5" barrel. The rifling tends to add a swirl to the shot patern, and it gets worse as the range increases. But with the laws the way they are, there is no help for that. A revolver with a smooth bore that fires shot shells would fall under NFA rules as a short barrel shotgun.
Standard Sidewinder in .45/.410
L5 Sidewinder in .45/70