1--listen to Miller, he knows what he's talking about
2--On a 4-in-1, check that the clam part isn't tweaked too bad. My 955K has a perfectly square and tight clamp, which is quite rare on these machines (as far as I've been told and have seen). If the clamp (clam) part doesn't fit tight to the blade/bucket part, it is almost impossible to get to fit right. And if it fits badly, that just messes everything up (it won't dig flat, won't carry fines...). There's probably a good reason it's only $350! But--it sounds like you are a metal worker, so you know the drill.
2--On a 4-in-1, check that the clam part isn't tweaked too bad. My 955K has a perfectly square and tight clamp, which is quite rare on these machines (as far as I've been told and have seen). If the clamp (clam) part doesn't fit tight to the blade/bucket part, it is almost impossible to get to fit right. And if it fits badly, that just messes everything up (it won't dig flat, won't carry fines...). There's probably a good reason it's only $350! But--it sounds like you are a metal worker, so you know the drill.