I have been using the liner-less compression shirts as a base for years. The ones with liners are too warm for me. I can get by in the winter with the base layer, and a softshell jacket on most days. If it is really cold, below 0°F and down to -30, ive layered two of the thin unlined compression base shirts under the same softshell jacket and been plenty warm. I tend to only have to worry about fingers and toes getting cold, my core is usually plenty warm in the winter months.