I just - like last week- bought a sailrite LSZ-1. It is great, though I have nothing to compare it to since I had never sewn before. the LS-1 is the same machine, just no zig-zag. I can tell you that there were next to no problems doing a jib for my F-31. A couple things were learned but no problems with the machine.
I did see reports of other machines being very similar- if not the same- to the LS series but I decided to go with the customer service at Sailrite which has worked out very well. They responded to my emails within an hour most of the time (except after business hours of course).