As I sit here with a lousy cold and eagerly awaiting the arrival of my brand new Pentax 20-40mm Ltd WR lens (probably on Monday) I am wondering which lenses other Pentaxians consider their favourites.

So far, I like my 12-24 for landscapes, and have got some nice shots with my Tamron 90mm Macro.

I am realising that good glass really does make a difference, so I've bought the 20-40 as a walk-round lens as it is a zoom, a Ltd lens, and water resistant.

What are your experiences/favourites?