I have 5 industrial sewing machines. Singer 3 thread serger, Rimoldi 4 thread serger, Singer Fur Machine, Singer Walking Foot and Necchi Zig Zag. I have servo motors on the walking foot and the zig zagger and love them. I am not one that uses the machines constantly but when I want to, I feel I have so much better control. The cost of the servo motor is worth every penny to me. I did buy the needle down servo for the walking foot machine but you have to make sure the stitch length is not adjusted off the balance wheel. (see attached photo and sorry it's sideways). I had a Singer 107W1 like that so I could not get needle down. I seem to have no problems with either of the serger clutch motors but would most likely change them in time. The fur machine sews left to right and is really something to get use to and therefore will be the next one I change to a servo motor. You can very easily change the motors as they use the same carriage bolt holes and are a breeze to lift in comparison. We did order the 2.5" pulley and changed out the one that came with the servo motor which gives added control, but I would try it with the regular pulley first if you are someone that uses these machines daily. I have made everything from quilts start to finish on the industrial machines, canopy for my husbands camper, dog toys 16 layers thick, fur teddy bears 8", bullet holders etc. My friend came to make a quilt and used the walking foot machine for quilting straight lines and had absolutely no problem, and she never sewed anything before. I used the walking foot machine to straight line quilt fleece backed quilts with no problems. I love these machines and am very happy with each of them and the servo motor gives the extra control I happen to like. Hope this helps and doesn't make your decision harder.
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