Pretty much all my spinnerbaits are the R bend variety due to the fact that I believe  I've lost several when the line became pinched in the twisted type. What type wire are you guys using?  Are you concerned about pinched line? Or is it just me?  Thanks

I have both the "R" type and the closed loop type and in my early days of fishing, before I could ty a good knot, the closed loop kept the knot from moving very much. Now it doesn't really matter that much. I'm more concerned with blades and skirts. 

I have two baits that are closed bend and the rest are R bend. The R bend, for me, are easier to tune once tweeked by a fish.

I prefer R-bend.  Easier to tie a knot.

I don't really care but prefer the R bend. Closed eye are great for fishing around toothy fish because it's easier to use a leader with them. 

I have some of both and tie a palomar on spinnerbaits, the knot doesn't usually move around on either, so no preference.