Thanks for resurrecting the thread. I keep meaning to come on here and post some longer term thoughts on this but I don’t have the patience to deal with the search function :)
I bought one after the PSA (thanks OP) originally as something to slip on after a ride to warm up. In fact it has been my go to winter coat, replacing a succession of very expensive, quite warm but rather fragile down jackets. It’s my first pertex and pile jacket. I’d heard people rave about buffalo shirts but always ignored it. Now I’m a total convert. It seems to work by having an almost totally windproof outer that traps air in the pile lining. Up here (NE Scotland) it does tend to be the wind that gets you, so this actually works better than the baffled down jackets. Plus it still keeps you warm when it’s wet and when it gets grubby I can just chuck it in the washing machine.
Don’t get me wrong, if you care about packed weight or size you still can’t beat down. But for day-to-day wear this pertex and pile design suits me much better.
It’s not waterproof in a strict sense and wouldn’t be a good choice for standing around all day in the rain. But if you are going to remain active then it works fine. I’m just back from walking the dogs for an hour in the rain and it was fine for that. I’ve also hiked all day in grotty Scottish mountain weather with just a base layer underneath.