To compare Paclitaxel eluting Zilver PTX stent (Cook INC) with bypass surgery using PTFE graft to proximal popliteal artery in the treatment of long SFA obstructions in a prospective, randomized, Finnish multi center trial with consecutive claudicant and chronic critical ischemia patients. Bypass with a synthetic graft instead of autogeneous vein is used as a reference standard because of the difficulty to standardize the quality of available vein and because the bypass done to the proximal popliteal artery with the graft types gives very similar results. The aim is to randomize altogether 400 patients during about two years in five university and in 2-3 central hospitals.