Damn, zappos is fast. I ordered the nuclei in a M and L to decide between along with a thermostatic hooded in a M. I'll write up a quick comparison when I get the thermostatic, and let you know which I decide on. First impressions of the nuclei is that it seems pretty warm for a synthetic. I don't think it feels quite as warm as the xenon did when it was new, but thats pretty subjective, and it seems darn close. I was hanging out outside for about 10 minutes with the temp hovering just above freezing with just a t-shirt and felt comfortable. Thats about what I expected, but its a good indication that it will do what I need it to. Cut is better than the xenon, better articulation and longer sleeves for when I'll be climbing in it (hopefully not often!). The zipper is smoother, bigger and seems more durable than the xenon, which was the final nail in the xenon's coffin after adding about an oz and a half of duct tape for tears, and losing a good deal of warmth. The size M is to spec 10.2 oz with stuff sack, and the L is 11oz. The sleeves are long, and the M fits my 6'2 170lb frame closely, but I think between these to sizes, I'd go with an L for more coverage and so I can layer my light down puffy under it when needed. Anyway, this may be TMI, since there doesn't seem to be much interest around it, but I thought I'd chime in since I'm happy to have found a good replacement for whats been one of my most used and favorite pieces. I'll post a quick comparo in the gear section when I get the thermostatic. Also, if anyone wants a size M nuclei in red, I'd send it to you for $145 including shipping, since I'll have to pay shipping to get it back to zappos anyway.
Activejunky.com is good too, with deals like %8 cash back at campsaver, %12 at backcountry and %13 at moosejaw. I've gotten a couple payments to my paypal so far.