Turtles do fine so long you get the right material, polyester not cotton. The cotton crap sticks to your skin even after you wash it, not good for a guy like me who has facial hair. The turtle keeps my neck and rest of my face up to the goggles warm. I usually don't cover my nose up since it feels stuffy and most of the time when I get off the lift and get moving you get warm when boarding and don't think of it so I don't cover my nose up using it that often.
The only time I use bandanas are on my head after I get off the slopes. UA does keep you warm as hell I will say that. Got the thermal ones for the legs last year, never wore jeans again under my snowboard pants. Going to get a sweater version this year and maybe the hood.