I would just like to express my extreme distaste for digest-sized manga trade paperbacks. I understand it's far more economical and it would be difficult to publish a lot of these really long series in larger books, but I just hate how tiny the artwork is printed. I'd much prefer regular comic-size collections.
THAT SAID, I don't really read manga. Partially because I hate the printing format, but mostly just because there's never been much to catch my eye. I bought and enjoyed all of Hellsing, though, and hope the future (prequel?) volumes get published here. My brother's also been collecting Berserk, and that looks insanely cool from the little I've flipped through it, so I'd like to get through that someday.
I also bought a Mega Man manga collection. Haven't read it, but the art looks amazing. (It's the series from the early 2000s or something, not the '80s series.) And, I bought and sortofkindof enjoyed the first Vampire Hunter D manga volume. I haven't gotten any more because I still haven't read beyond the first book, so I'd hate to "spoil" the books by reading and looking at watered down versions of those. The first manga volume is kind of wonky...kind of a weak adaptation. Yet there's something about it I kind of enjoyed and would like to collect the further volumes eventually.