The Obukowin portages are in great shape and used a lot. I traveled them in 2015 and had very little to clean off the trails. Trappers use most of those three canoe portages in winter so they keep them wide enough for their snowmobiles. You just have to make sure as you head north on the middle portage that you head for solid ground and "Stoneman" and avoid the trappers winter trail through flat but boggy ground.