Welcome to SRP. I like all of the sizes but truth be told I probably like the 5/8 best. Just my personal preference. I like a hanging strop better than a paddle for daily use and a silver tip badger best. All of the above is a matter of personal preference and you won't know until you try. On the heat treat the razors you mentioned are all high quality and should be fine. If you're worried about the spike point go for the round. They don't look cool but they shave nicely.