If americas ADA distributor (I'm pretty certain it was senske) isn't stocking ada II because he believes it to be inferior it's probably time to worry. For a long time it's had a reputation to turn to dust and for the water to never clear as a result, even in the most careful of persons tanks.
Personally I'd go for the florabase, cheaper and just as good stuff, possibly better as it has a much less pronounced ammonia spike. I've used both and personally prefer florabase.