I presently own and shoot a 1925 vintage Ideal Grade 12-bore with a HOT unit; this gun has obviously seen some aftermarket tampering, but the trigger units works great and without a hitch. I once got a deal on a 1912 vintage 3-E 12-bore because the HOT unit on that gun didn't work at all. The gun was sent to Jerry Andrews for a trigger repair and I shot the gun for years afterwards with no other issues (still regret trading that Smith). I've owned several other Smiths with the HOT option; and the only problem ever encountered with any was with a beautiful A-2 Grade. If I selected right barrel first, the gun would double; if I fired the left barrel first, the trigger unit worked fine. Not wanting the gun tampered with, I left the gun AS IS and used it quite effectively with the left/right firing order for years.
And as I prefer double guns with manually operated safety slides, let me add also that one thing I really appreciated about the Smith HOT unit is that it won't allow an "automatic" safety feature (maybe when used on other makes, but on a Smith gun there is not enough room after installation for the bar that connects the safety slide to the top lever). So when shooting clays, or in a late season dove blind by myself I never have to be concerned with losing a shot because I either failed to remember, or improperly manipulated the safety slide (some will consider this practice unsafe; so I don't encourage anyone to follow my personal preferences).
Last edited by topgun; 08/20/15 08:57 AM.