Have both a ST 7 and ST 8 and both working-rebuilt by me. The ST 7 was problematic since the drive wheel on the arm drive shaft had a gum rubber wheel which disintegrated probably withing ten years. I replaced mine with a neoprene rubber VCR wheel made a few adjustments and never had another problem in twenty years. They are a little touchy with the automatic pick-up and shut off. The ST 8 is superior machine with a carbon fiber arm drive wheel and and extra belt to propel the arm. I use this one as my daily driver and use it to transfer my vinyl to CD with a Shure M3D cart at 3 gms (for mono LP's and early stereo). I have lots of TT's including Thorens 124's, multiple Empires, Gray's and Rek-O Kuts but I like the HK ST 8 the best since there is virtually no tracking error. They were probably the best linear machines made-better that the B&O and as good as the Rabco and Revox.