Back relief helpers work better when they are rounded. That is why they come that way from the factory.
Here's some info......
There was a point in this Ad somewhere, FLAT and a big ass slot, and additional grooves does Not
GLIDE very well, nor dry very well, so is it really a stair glide?
Honestly..it's kind of the Anti-glide, let's see if Mikey would like that on his
Vortex?
As for wear, keep your teflon glides Round as best you can, a little block of wood and some 80 grit or a Rasp will make short work of keeping them round, then follow with some 120 grit, it'll also clean them up nicely. keep em' round and they will push easier and extract better.