I have been doing a bit more tying than usual lately, and have been experiencing lower back pain after 30 minutes or so. I realized that my vise head is a bit lower than my head when tying, and I may be hunching over a bit too much. I also might be sitting back a bit too far, and perhaps leaning in to get closer (my vision ain't what it once was). The height of my desk (and vise) is fixed, so I guess I may need to get a lower chair, or cut off the legs a bit, but I do not particularly like one on wheels either. For you tyers who spend quite a bit of time tying, should the vise be at approximately the same height as my head, or is it simply a personal preference? I've never really thought about this stuff before, and I hope it's not too silly a question. Thanks, in advance.