So now my quandary is do I make more 3s for the people that wanted 3's or do I make all Gen 4 now...
I like the simplicity of the Gen 3 vises. The large radius shown on the Gen 4 may appeal more to guys doing special filing: race chains, square, etc., and kind of remind me of the Gen 2 ones. Waiting to see what a Gen 4 really looks like (is it 2 pieces or 3?) and where you price it.
If you are willing to make all of these variations (different 'Generations', aluminum or steel, wing nuts or levers, plus adaptations for the various filing guides) it is a great value to your customers who may want to customize their vises according to their needs. If it becomes too much for you, then maybe you standardize on a few models, and offer a few options.
I think that the affordability of the Gen 2 vise is also attractive for a lot of folks, so hopefully you will keep a basic model in the line up.
These vises are long overdue in the market, so thank you again for making them available!
Philbert