Yes the Minosharp is a better sharpener than either the MAC or Fiskars Rollsharps.
I've handled a lot of MAC knives and have owned a few over the years. But, while I've bought four MAC Pro chef's knives for other people, I never bought one for myself. That isn't to say I haven't used and sharpened plenty of them.
Not all Japanese knives come OOTB with good edges, and of those not many are as consistent as MAC. I'd say that MAC Pro ships at about 80% of its potential, which is significantly sharper than you could ever get a Wusthof or German made Henckels -- but that's very rough and subjective and you shouldn't be fooled by assignment of a numeric value. There is no meaningful sharp-o-meter beyond cutting onions.
If you want maximum sharpness, the best ways to get it is with bench stones or one of the uber rod-guided tool and jigs like one of the Edge Pros, or the Wicked Sharp. If you want the best edge you can get without climbing a steep learning curve or dealing with a lot of tedious set up and take down, your best best is one of the top of the line Chef Choice machines.
Everything else is less. You're asking, I'm telling you, but it's your choice. If you need to sacrifice some sharpness or edge refinement to save some money, for convenience, or because -- for whatever reasons -- you don't want to learn to freehand those are some powerful reasons. Not that you need my validation.
Over the years, MAC Pro and Masamoto VG have been my most frequent recommendations. I don't think that anyone who bought a MAC on my advice was ever burned -- at least not after letting MAC customer service deal with the few problems which did come up. I like the knife a lot -- but in all honesty wouldn't buy it for myself even if I were looking for a mass-produced, stainless Japanese knife in the price range; I'd go for the Masa because I like its profile so much. What can I say? I'm a huge fan of Masamoto chef's.
But... if you're gauging the quality of my advice against my personal experiences and preferences, I wouldn't buy a mass produced, stainless, western-handled chef's no matter who made it. I'd either buy carbon or tool steel. From the early reports -- and it's too soon to tell the Kagayaki CarboNext (tool steel) is an excellent value and very nearly the equal of the Kikuichi (fomerly Ichimonji) TKC, which is an outstanding knife with epic edge holding.
I'd certainly consider those, but probably stretch the budget and buy either a Masamoto HC or a Tadatsuna White #2 (carbon) yo-gyuto. But that's me.
The last time I bought someone else a Japanese made chef's knife, it was a MAC Pro for my Dad's girlfriend about a year ago. If I were buying it for her today, it would either be the Kagayaki or TKC.
Hope this helps,
BDL