Best tubes and valve length?

proto
proto Posts: 1,483
edited August 2007 in Workshop
Need some new tubes for my best bike. Any preferences?

Have recently been using Contis but stems are threaded all the way up and they play havoc with the rubber seal in the chuck of my Silca track pump. I think Scwalbe valves are plain/smooth all the way up which must be better. Maybe. Any opinions? Scwalbe Extralight, Conti Race Light, Vredestein, Micheli Airstop Ultralight? Buytl? Latex?

What's your poison?

And can I get away with 40mm valves on Mavic Ksyrium ES wheels, or do I need to go 60mm ? Ta!