To me, the most "eco" lubricant is the one that extends the life of the lubricated parts the most. If you use a biodegradable lubricant that isn't as effective a petro-based lubricant on your chain and, as a result, the chain doesn't last nearly as long, that's be a step backward for the environment. If you have to apply it a lot more often than a petro-based lubricant, the environmental benefit could be in jeopardy.
I don't know anything about the product named, and for all I know it could be a better, longer-lasting lubricant. I'm just saying that environmental benefit claims for products can be difficult to evaluate.
I use silicon/teflon lubricants a lot and they do well in cold weather. I have used various bike-chain specific lubes and they have generally worked ok in cold temperatures as well. I rarely bike below 15F, though.