I love the Siren, alot more then I thought I would. I use it quite a bit, and it's the first (and only) LC200N blade I own. Edge stays sharp with weekly stropping so far (I've used it for about a solid month's worth). It's one of those knives that I like more and more, the longer I have it.
I just use it for daily chores like cardboard, straps, rope, scoring, as an awl, blister packs/packaging. I also carry it at work when I know I'm heading to some of the less attractive parts of the city.
I agree that it's the smoothest backlock I've ever owned(I can close it one handed). Some of, if not the best fit and finish on any USA, Earth Spyderco I've owned. I personally like it being liner less and the fold over black wire clip. I used to think handle was a little long, but the more I use it, I don't think I would want to change anything about it. I also like where the thumb hole is on it too, keeps for a low profile and easy opening. And the deep choil behind the pivot makes for a very comfortable handle, like a Fred Perrin kind of design.