Bruce,
Of course, I haven't particularly worried about reproducible lengths in my rifle because whatever I use is well too short. But both brands of brass have fireformed very well, with pretty even case mouths after opening and no failures upon forming.
But I don't really see any "safety" issue with the shell lengths. If you want to make sure all your cases are even at forming, you ought to plan to trim them to 2.84", just to be sure. If you want every last iota of length, it might be best to find a shooter with a .40-90, lay in a supply of shells, and have him fireform them to see what the lengths are, and then trim to the max possibility and order your reamer and dies accordingly. I don't know how typical my small samples of German brass would be of the brass you may wind up getting.
Bertram quality ranges from barely there to annoying but acceptable, depending on caliber and vintage. The.40-90 has been in the latter category; after a thorough annealing, the main irritation has been varying length. (You might be in a better position to pound on Bertram's desk and give him what-for than we are; the Home Market ought to be of more concern than the barbarians in foreign countries that accept any trinket offered.

).
Most of my Bertrams have stretched out enough to reach max length and more by the use of paper patch bullets and black powder. I've yanked a few in half by being careless about drying the chamber, but that isn't Bertram's fault, and there seems to be enough brass in the walls so that the shells can be "drawn," as it were, into the leade and trimmed back. I've either gotten a lengthened shell to trim, a two-piece shell, or a "kurtz" shell with the bullet having dragged the front part out the barrel. No stuck front ends in the rifling yet; knock on wood. But this lengthening seems to be a peculiar hazard of long cases and paper patched bullets; something to keep in mind and to have a contingency plan for. By the way, they are cavernous; I can drop in 100 gr of powder with plenty of headspace left.
As for the mutant .40s based on the .405 Basic brass, they've made things convenient for some people at the expense of throwing the rest of us into utter confusion. The thick rims and narrow bases of these shells generally make for an expensive misfit in original chambers, and nobody but the "stuck-ee" who has gotten the wrong brass or rented the wrong reamer seems to be unduly concerned about this.