I don’t think there’s any better base layer in the cold than good merino wool. I’ve got them from LL Bean, Smartwool, and Outdoor Research I don’t find a big difference in the brands as long as it’s from a quality brand. Personally, I prefer ones that are quarter zip with thumbholes. The quarter zip is nice if you start to get hot. The thumbholes are just for convenience so the sleeves don’t ride up.
I don’t think there’s any better base layer in the cold than good merino wool. I’ve got them from LL Bean, Smartwool, and Outdoor Research I don’t find a big difference in the brands as long as it’s from a quality brand. Personally, I prefer ones that are quarter zip with thumbholes. The quarter zip is nice if you start to get hot. The thumbholes are just for convenience so the sleeves don’t ride up.