The best thing to do for sizing the boot to the waders, is to take your waders with you to the store. Even biits within the same brand will vary a little bit. I like to have enough room to fit a pair of polypro liners, and a heavy wool sock in mine, with a little room to wiggle. Not too loose, as they will bunch up in the toes and heels. It really helps to have the extra wiggle room for winter fishing. I fish alot when it's below 20 degrees, and three feet of snow on the bank for winter steelies. If your boots are too tight, you'll suffer. The best for absolute zero weather is till boot foot neoprenes with a felt inner liner. I have a pair of cabelas titanium neoprenes, and they are great when it is stone cold outside. When our weather is like a blast freezer, I still get cold feet in a stocking foot wader of any type.

My friend has those rubber gripper soles on his boots, and they work well even on slimy limestone bedrock. There are no substitute for felts with carbide cleats, but that would be death on a boat angler. Too dang noisy. I am a Midwest bank maggot, as the rivers I fish, won't float a boat in a lot of stretches. If your strictly a bank angler, my vote would be for the felts and studs. They are nice for skipping across slimy wood in the water. (It's been a long time since I was light enough to skip. I kind of waddle at an accelerated rate)

Any way, this information won't be worth enough to buy you a cup of coffee anywhere, but hopefully it helps you with your fishing.