Well, I'm a pinner because I believe I get better results that way. I have friends who go to remarkable lengths to never pin. Our end results look much the same. Even though I pin and have extra steps that way, and even though I prefer to cut large so have the extra trimming step each time too, I'm generally considered to be a speedy piecer and finish projects very quickly, typically faster than my friends if we are working in a group setting.
I have a Bernina 820 (currently in shop, non-related issue). It has the built in walking foot option as well as the BSR. I'm pinning anyway, but don't see any real huge difference in using the walking foot for basic initial seams or not, but I typically keep it in walking foot mode as my default because I do feel it makes a difference going over the lumps once I'm putting in a piece with a couple of seams. My friend who gave me the Bernina also kept it in walking mode.