The first thing that struck me about all of the planes except the Spiers block plane was how uncomfortable they looked to use. I know that old is often held up to be better but would we seriously pick up one of these in preference to a good modern plane, but of course thats not why they are collected.
Hi James, surprisingly mitre planes are quite comfortable to use. With the iron bedded at 20 -25 degrees plus a 30 degree sharpening angle and a very tight mouth, they excel at planing tricky grain which a normal plane wouldn't handle. Of course they are also great on end grain with a bevel up blade and plenty of mass. You are right about all these though, I've never used any of them and for me they are just collectable. All the best, David.