Rapha, nice but a bit pricey?

Yeah, I don't go back home that often at the moment. But I have an amazing merino hoodie I got from there years ago that is a great all year round piece of clothing. Do they do anything base layer specific though?

Not specific but I tend to buy down a size or two so it is stretched thin and closer to the skin. I get tank tops for under jerseys or long sleeve for just that and a jacket.