Personally, I enjoyed the Ant-Man volume (which I bought in hardcover), although I preferred the Ant-Man tales better than the Giant-Man ones. That may be just because I like shrinking heroes better than growing ones--there's more you can do, storywise--but in any case the majority of the book is Ant-Man.

Just got my copy of FF Vol. 9 today. Haven't started reading it yet but I flipped through and I'm extremely pleased with the quality and the stories look awesome, too! A long Dr. Doom arc and then the Thing in space? Can't wait! Also got the Superman Family Vol. 4 Showcase, which also looks like it'll be a super-fun read.