Rapha, nice but a bit pricey?

Bear in mind the merino arm warmers aren't quite as warm as the fleece-lined type. They're more comfortable, and usable for more of the year, but on a few cold autumn days last year I was wearing base layer + jersey + bibs + winter tights + merino arm warmers, and a wind jacket on over the top, and not taking the jacket off. And that's SE England.

They layer really well though, basically they're like having a (removable) merino base layer on your arms.

This is why I have a mind to get a removable sleeve jacket as opposed to just a gilet. Cheers.

Looks like the Montane Featherlite velo I keep stashed in a pocket for rain. Very light and keeps the chill off, though I wouldn't want to use it as an everyday winter jacket.

There are some discounted closeout shells in odd colours around town in Snow+Rock and the like at the moment.. quite tempted. eg Arc'teryx Beta SL, North Face antimatter 40% off. Still spendy but almost justified if used 5 days a week all through winter.

I've only worn the Montane once. Its a 'just incase' carry along.

I'd get the Arc'teryx Beta SL. Spendy. But its functions well above its weight and comfort. Been close to pulling the trigger on that exact jacket myself, and up her we take are wet weather gear very serious.