Xlab Superwing

[Newboy]

Has anybody used any of the XLab bottle cage mounts on a mountain bike? I am specifically looking at the Superwing or Turbowing that can take 2 bottles plus some spares.

 

I am considering this as:

 

a) my frame don't take any bottle cages inside the frame; and

b) this system attaches to the seat and not the seat post, which will enable me to still use the KS Lev dropper post that is in the drawer.

 

Any advice or experiences with the above would be appreciated.