I work for a large straw contractor and we ran several 6000 and 4000 welgers..... all i can say is i'm glad we moved to class.... the last season we ran 3 6000's, it was a miracle if all 3 were out the yard at once. the plus points were a good appetite especially in silage and high number of ram strokes per minute. bad points. you had to keep it heavily fed to make to fill the top of the bale which in turn made it hard to get a decent weight in the bale. the stress on a weak drive line due to this caused us alot of problems. firstly the pickup is very lightweight, we lost cam followers for a past time ( while being very careful not to run them low) pickup bands also very lightweight, the mid post on the pto's were forever breaking up. we tried everything to absorb some of the vibration but to little avail, i spent alot of time welding these back together. electrics were just an absolute nightmare. we ended up running 1 6000 and 1 4000 without electrics at all which actually improved them no end, just set the pressure on the valve when you start and enjoy a trouble free day. we baled 2 sets of needles that year, one set went when a peice of flint got stuck in the ram and obstructed the needles which broke the driveline and BANG, and one set where i drove under a branch and the knotter gearbox which has a small opening on top ate a small piece of twig ( and i mean a small twig) which got between the gears and threw the timing off, BANG. you generally aren't looking at just a set of needles either it generally causes some major destruction to the needle/knotter driveline.(over the years we had several needle sets lost mainly to foreign objects and driveline failure in five years of claas 2100's and 2200's just the odd bent needle.) we also had 2 flywheels come away, one while at full tilt which caused ( my best description is) one hell of a mess. general maintainance is rather excessive and often awkward. i invested alot of time every morning stripping, cleaning (especially the retaining cones, loosen and clean with a pick set) and resetting the knotters. the lads who didn't had trouble all day. i got very quick at this and often stripped them halfway through the day as well. she hardly missed a knot then. i've driven claas, vicon, nh and hesston as well and although all have their good and bad points the welger is definately the most high maintainance. give her alot of tlc and hopefully she'll see you through without much grief