I'm still new on this site and have only done a few things outside of belts.
But I started belts and holsters in 2012. So I have some experience but not as much as others on here.
So far i've had the best luck out of the acrylic finishes.
I've tried the water based and didn't like it at all. I've also used Fiebings pro leather dye and really like it a lot.
The oil dye was good but seemed like I had to wait 2-3 days for it to be completely dry.
So if you are not rushed on time at all the oil dye from my experience will provide a very even nice color but it can take a bit.
The Pro leather dye I wait about 3-4 hours and buff out really good.
I also die the leather before burnishing the edges because I use Gum Tragacanth and that can keep the dye from working too well.
So far with my belts even if I dye the inside I have dyed it, finished it then put some neats foot oil to soften it.
My experience with the Pro leather dye also is it will stiffen the leather a little but just a little bit of flexing while it's drying keeps it nice and pliable.
After the neats is all soaked up I buff it out again and apply fiebings snow proof and it's ready to go.
That's just what I have done so far and some others may say it's all wrong but I haven't had any belts bleed yet.