I already have a crank stringer. At one point I thought about replacing crank with the wise. However, for the reason like you and many other threads related to Wise, it seems to make sense to get a stringer like Stringway ML100 if one was thinking about a WISE.
Not much to go wrong on the ML100 because it is a drop weight machine. Approximately $1200 for a new machine vs $500 for the add on? I would go with the Wise. I like the functionality of the Wise with the foot pedal. The pre-stretch option is awesome.
I was leaning towards the MS200 but then someone posted a recent thread about problems with tension settings. *sigh*
I have strung a 1,000+ racquets with the Wise and it died. I guess that is pretty cost effective when I look at the big picture. The newer tension heads from Wise are supposed to be improved and come with a diablo.
On a positive note they really do honor the warranty. They replaced a defective Wise no questions asked and it was at my door in a few days.
Despite this most recent problem with my Wise I would make a purchase again. Don't shy away from the machine because it is a good addition to a crank.