Some people find Globals difficult to sharpen. I personally do not find them much harder to sharpen than other blades. However, if I had to start over, I might have gone with a different knife, since Globals are relatively soft for Japanese knives, and do not hold their edge as well as a result.
On the flip side, Globals are extremely corrosion resistant, and I find that they are extremely handy for citrus, pineapples, things of that nature for this reason. I use it without using a cutting board. As a day to day knife, it will require more frequent sharpening than the Mac.
I would also consider other knives such as the Fujiwara FKM if you're looking for an entry level Japanese knife.