What is the biggest pro for using this vs a plastic bucket-style fermenter?
In the greater scheme of things there is no huge difference. I like the stainless steel because it's easier to clean and sanitize. The conical shape on this fermenter minimizes contact with the trub, but that's not a huge deal either since I rack to secondary on most of my ferments. This particular fermenter is a lot easier to get the lid on and off than the plastic buckets. Since I have also put together a chest freezer with a temp controller for fermentation control, the stainless steel will cool more efficiently than plastic, so it's a bonus in that environment.
Whether or not those 'pros' are worth the price in this case is up to the buyer. Will this device make a measurable difference in my end product? Probably not. But since homebrewing is a hobby for me, having nicer equipment makes it a bit more fun for me