Product review (3 stars): If you are looking at tips you might want to check your bottom rack for damage.
A little hard to go on but if you keep wiggling them they work.  Wish I had applied them before the tips started rusting through the original rubber coating.  I ended up using them on all the tops that I could so it would look uniform.

I am also using ReRack.  I suggest you start refurbishing as soon as you notice some wear and you will have better luck.  I did not realize that some of the metal/wire inside the rubber was almost completely gone from rust.  Take out your lower rack and turn it over and you might be as surprised.  I would think if you need tips you might need touch up as well.  (Racks are expensive if they have yours)