I've honestly not seen a bit of difference, other than comfort. I have a pair of Alpha's and have worn them for one full season. I did not like them a bit, but I wanted to see if there was any advantage.

This year I wore my Irish Setter leather boots. Now, I did scrub them several times and then stored them in a box full of fresh earth for a couple months after I bought them.

I saw no difference in spooking deer. I had a small buck come in under my stand one morning and sniff around, then walked behind me down the same direction I walked in that morning. He sniffed my tracks a couple times, then continued about his business, never spooking. That tells me that rubber boots are not neccessary. Take care of your leathers and keep them smelling like dirt and you'll be fine.