Oil stones are marginal for Globals. Water stones are better. Despite the manufacturer/retailer's (true) claim that the Wustof stone works as well with water as with "honing oil," the Wustof oil stone IS an oil stone, way too coarse for your knives, and generally NOT a good choice for your Globals.
Globals are made with a proprietary alloy developed for Yoshikin (who makes Global) called Cromova 18 which is very tough because it has so much chromium; but it's also fairly strong and Yoshikin/Global does a good job of hardening. Global knives can be sharpened profitably on good oil stones (there are better choices than the ones branded as "Wusthof"), but slow stones are highly problematic for beginning sharpeners, and even very good oil stones run slow compared to good water stones.
Globals sharpen better on water stones -- the faster the better. The Global/Minosharp brand is not a bad choice -- although in the US they're overpriced for what the are. But you seem to have an affection for things Global so the branding might be enough of an extra to justify their purchase.
In any case, you should start learning with two stones, one medium/coarse (around 1,000# JIS) and the other medium/fine (around 3,000# - 5,000# JIS). After you've learned to sharpen with those, you can add a coarse stone for thinning.
If you're like most people, it will take you quite a while to sharpen better on bench stones than with a MinoSharp Plus3.
BDL