Which Mothers products specifically are you talking about? I have a lot of Mothers products and have always liked them. You really can't go wrong with Mothers. I just happen to usually prefer Meguiars. You might want to head on over to www.autopia.org and do a search for "mothers" and see what you come up with. There is even a Mothers rep there, he goes by the userid forrest.
Meguiars has a 3 step system called Deep Crystal. The Deep Crystal Carnauba wax is step 3 in that system. This would be comparable to Mothers Pure Carnauba. You should be able to find both just about anywhere.
meguiars, imo is the best for the money, and then some. ive always used #7,#9, and #26 and my recipe for maximum paint looks and protection.
I recently tryed 2 new waxes that are my new replacement for the others mentioned. I used 1 coat of Klasse all in one and 2 coats of meguiars nxt. on my 4 runner. Nxt was very easy to work with, no white residue, just make sure if you go the nxt route to apply thin coats rubbing it in real good. you will be hard pressed to find a better product. as far as durability, im not sure, as i stated this was my first time using it and seeing the results first hand. i bought the Klasse for durability, this is my first time using it, but have first hand knowledge that the stuff does what it's advertised to do. (my dad uses it)