If people are still curious, the S model all has brass as base material with steel being used in stress points. The difference between S and the L, other than the price, is the L is not waterproof. Class S claim to fame is that due to the O rings and the barrel covering the flint (kinda like a safety) you can submerge it in water for up to 5 minutes and it will still light. As for EDC, if you are using it to start fires for camping ect, it may not be your best bet as the wick is very recessed and from what I've heard if you leave it alight for a prolonged period it will be very very hot to the touch not to mention you're risking the O-ring being overheated (they do sell replacement O-rings and wicks and flints). The base model actually comes with a mini fuel reservoir and back up flint as well. Over all its a very cool product and I would love to buy one if this poll ever makes it.
Here and elsewhere it looks like the "L" is available in stainless, but the "S" is only available in aluminum and brass with (or without) various finishes. Is that the case? I myself prefer the naked brass, but a friend who's concerned mostly about durability asked.