The counters you do get are quite nice. There are a few, (though very few) minor revisions in the Ch H - a slightly changed RF here and there, some reworking of the MAVNs to reflect the new counter scheme, basically. The Ch A revisions basically have to do with the new colour schemes, no other changes that I can see.
Some scenarios have been reworked slightly from the original, but no biggie.
So really, as nice as it is, you could probably get by without it.
EXCEPT....
Dinant. Dinant is a CG unlike any we have seen before, just based on the river crossing rules alone. Add in some really interesting campaign VCs, and the fact that there is no movement or re-setup between scenarios, and this has the potential to be a truly epic HASL.
Plus, you get 10 or 11 Dinant scenarios, too!
Look at it as buying Dinant, plus you get a bunch of extra stuff. Whether Dinant plus is worth the money is up to you.