In terms of friction on my Kai.g3.
<Least to greatest> All mice are in between 100-110G except the G500.
Deathadder BE = Mx518 Rev.1 w/ Hyperglides > Steelseries Teflon feet for Ikari Optical (Prefect. Not that fast, not that slow) > Intellimouse Explorer 3.0 w/ Perfect glides (feet are few months old) >G500 w/ Stock feet (borrowed).
I don't know about smoother, but there is a lot more noticeable friction with the G500 and 3.0 w/ PG. Granted, this is my quickest pad, both feet feel like they're dragging when swiping.
Now if I were to switch out too my QcK+ and or Raindrop XL, I would agree with you about the smoothness factor, but were mixing friction and friction here and movements are just too sluggish for my desired CM/360 and developed muscle memory. I'd much prefer Hyperglides and or Razer stock feet in this situation if you get what I'm saying.