Never, ever, going to buy artificial material baselayer garments ever again... never.
Why?
They make the body sweat sooner and they begin to smell very quickly.
So what do I recommend instead?
Merino wool baselayer garments. I'm wearing mine right now.
Not only does Merino wool not cause the body to sweat more than it should, and not smell at all when you do sweat (even when you have worn it day after day after day under work clothes and night after night in place of pyjamas), but it also can be worn in a wide range of temperature environments.
I wear my top and leggings under my motorcycle leathers in both hot and cold climates, under my work clothes, and sleep in them during the coldest months of winter (gets to be -5C at night here in Canberra, Australia). And they are great under wetsuits (and also drysuits).
Every time I read or hear about people purchasing cheaper artificial baselayer garments like Skins or Thinsulate I can help but think it is false economy.
My friend put me onto Icebreaker Merino Wool (very cool site, too):
Icebreaker
Made from New Zealand Merino (actually they are manufactured in China... but they state this on the website and go into why this is not a compromise... very strict management of quality control standards and adherence to specifications.
