Horizontal baffles are probably the most popular method of orienting the baffles in a sleep system. It has been used for a long time. While vertical baffles, if sectioned off properly, will keep the fill in place better, they are time consuming to build. Horizontal baffle systems are much more time efficient (cheaper) and can perform quite well. Using a generous overstuff helps keep things in place and a little attention by the user to make sure the down fill is distributed well before camp can make for a warm and affordable sleep system.