It was my sister - who lives in LA - who first introduced me to Uggs. All the surfers wore them after surfing. She bought me my first pair as a xmas present. I did not wear them for a few years, thinking they were ugly as sin!
But like you, eventually I caved because my toes were always freezing cold. And, we get so much snow here.
I would *highly* recommend you buy the REAL Uggs. Accept no substitutes! There is a difference between the knock-off's and the real thing. The real thing are a lot warmer, softer, more flexible, etc.
But if you go with one of the more "fashionable" styles, be careful. For example, I have these, which I think are cute:
http://zeta.zappos.com/product/7329357/color/106
But unfortunately the bottom has no sheepskin lining, so they aren't quite as warm and cozy.
Here's the other thing about Uggs: you're not supposed to wear them with socks! You have to go sockless with them - they are warmer that way, believe it or not!
In fact, while in Iceland, I tried them with socks - a new pair of socks from 66 North - and after just 30 minutes tromping around the Geysirs, I thought my toes were going to fall off from frostbite. Once I removed the socks, I was perfectly fine and toasty again - and able to tromp through snow for two hours around the waterfalls.
As for your Reynaud's, I think your feet will thank you for the Uggs. You can still swap out into more fashionable shoes once you reach your destination.