A friend bought a HF 20T and it was not square. He bought it only to cut leather patterns with. He brought it to me and I squared and plumbed the bottom cross members to the top and welded it. Even the adjusting holes for moving the bottom up and down were off at least 0.25". Now it cuts evenly, is non-adjustable, but he only does one thing with it.
I have a larger straighter 20 ton that I bought from a tool supply--if you are around Charlotte you are welcome to come by to use it.
