The CarboNext series is one of the really good values in the knife world.
They take a great edge and hold it for a long time. That said, there has been a long standing issue regarding the quality of their out of the box edges. A significant percentage (but by no means all) come from the maker with really bad edges. So bad, that they can't be fixed with a mere touch up on a high grit stone, but must be completely reground. Unfortunately, JKI's extra-cost sharpening service is useless.
Putting a decent profile on a CarboNext isn't that big a deal. If you can't do it yourself, you can always take or send it to someone else and have them do it for you. Even running it through one of the "Asian angle" Chef's Choice machines is good enough. If worse comes to worst, you could always take it to SLT. Just make sure to tell whoever will do the sharpening that you want 15* angles.
There's some context that goes with all of this... A knife with excellent edge taking and edge holding properties won't magically transform you into a good sharpener.
If you are a good sharpener, you can probably tease some extra edge quality out of a CarboNext (as opposed to a Kagayaki Basic, say); but if you're not, sharpness will be limited by your skills and not the alloy.
Edge holding is very similar. If you sharpen an average knife on a once every two month basis, chances are you'll sharpen a better than average knife on a once every two month basis as well -- or, get another two weeks. In other words, not that big a deal.