It's good in the sense that any manga artist would look at the numbers and think, "Wow, that's great!" But it's not quite "a complete success!" yet. For example, there are many manga series currently being adapted into anime with much lower sales. At the same time, distribution of sales is also very important.
Personally, I believe the decision to discontinue the Grapara brand happened sooner than many people thought. In fact, I think the NTR (Netorare) scandal arose because of it, and the decision may have come from KA itself wanting to continue, or there might have been something going on behind the scenes, but I don't think it had anything to do with sales figures.
The funny thing is, if you take a peek at MangaPoke, especially the lower-ranked ones, you'll find manga with terrible numbers in every aspect, making you wonder how they even manage to survive.