By having both the outer and inner you can wear both or either by themselves.
I don't often wear just the outer shell, as without the inner they are a little big but the inner glove is great to wear on dry days or even off the hill when its cold.
With the outer shell the gloves do fit slightly bigger then most but the outer shell has a handy draw string on the cuff which both helps keep snow out but also helps the gloves fit under jacket cuffs.
A sachet of Nikwax Leather balm is included to help keep the palms in good condition although so far I have not had to use it.
The water proofing has been great so far and I have found the back nylon does not wet out in in the wettest conditions. The palm did get a little wet sometimes but never let moisture through to the inside. Treating the palm with the Nikwax would help with this I'm sure.
The inner gloves having individual fingers inside makes them pretty warm but even on warmer days I do find they breath well to help prevent overheating.
I would certainly say these are a more cold weather glove but having the ability to just wear the inner glove on its own is a big bonus to me.