DN1A is an alternative to DN1, both roads are crossing the mountains from Bucharest to Brasov. There is not so much traffic, especially during the weekends. Asphalt is fine, sometimes there can be dirt or sand on the road. From Cheia to Muntele Rosu chalet there is a short narrow road with tight curves that was recently paved. If not in a hurry it makes sense for a short detour.