I am going stay fairly silent on this one.
No, more exspensive does not mean better protection.
I am on the outward edge of trying tons of nubas with only a few more on my list to try.
I will say I like Swissol's Cleaner FLuid, very nice prewax with lots of richness.
For under $100, my favs (so far): Souveran, CG 50/50, NB, and Max Wax. I am beginning to use different waxes for certain things I am trying to achieve. Anymore, durability is not an issue. I assume hwen the Ohio winter coems, I will use Wolfgang sealer or Collinite, but for now I could care less about durability. Most nubas will render around 4 weeks of good protection +/- a few weeks depending on conditions. Of course there are exceptions.