Look for one that has nice inner padding/fabric that'll keep your head warm and comfortable. The ones with a cinch adjuster in the back look awesome to get fit dialed in too. Check if it fits nicely with the goggles you already have or are getting.
I got a protec classic snow, and it's pretty basic. It gets job done bit I wish I had spent a little more and got something nicer. It just has the foam pads like old bike helmets so I wear a balaclava under it. The newer protecs look a bit more tech and better now so don't rule them out either.
Like was said above, try on as many as you can and find one you really like! If you gotta wear a helmet you gotta like it!