As luvmytoolz stated before, I have two of them because of my workflow. I got my first one, modified the Zero degree base to fit a longer bit and try leave it set-up that way. After breaking down that set-up too many times, I got a second one. It's not totally sensical, because you can literally change the bit and switch to the vertical base and cut something different, then swap it all back....and not lose the perfectly flush trim. It really will do that! But to skip the headache, I bought a second one from a member here.
It was the most un-used used machine ever. (assuming you would call "purchased" from a retailer, but never actually used, then sold as used)
I keep them both as top drawer in my Sysport stacks. They are that important to me, but I'm a pro in a busy cabinet shop, using them frequently. Like the others have said, they really shine with edging, but they are not a one-trick pony. The off-set of the vertical base makes them very stable when used for any other type of edge treatment; round-over, bevel, ogee, etc.
I also have two OF1010s, in a similar situation. One is set-up with a copy ring (guide bushing) and a specific bit, which never changes. The other is more versatile, getting changed more often.
I have all of the parts to do the horizontal trimming with the OF1010 too, but that was really just as a back-up before I got the second MFK700. It was that important to have that ability if something would happen to the main one.
My first MFK700 was destroyed in a fire several years ago and it was one of the very first things I replaced, along with a DF500, and RO90.