Hello Bill,
I won't comment on the one in the classifieds as I haven't checked the ad.
ML7 is a cost effective route to a 'classic lathe'.
Personally although the s7 is a better lathe I don't think the difference in performance is as big as the difference in price often is.
Always worth looking for one that comes with a set of accessories as the essentials can cost more than the lathe if bought individually.
Also keep an eye on the classifieds in the magazines.
Neil