when i went to bigger machine kept my 83 6620. has 3800 hrs on it, but it is a good machine, can handle a 6 row head easy enough. easy to find parts for, relatively easy to work on. not a lot of electrical c...p on it. if that size machine fits your operation think you will be happy with it. check the unloading auger in grain tank (vertical one) for wear. bottom tin on feeder house. reverser gear box. clean grain elevator. chopper(best if it has slow down kit if doing corn). good luck