Usually I buy digital since it's much easier that way, but recently I've been wanting to have a few of my favourite stories in printed collection, so I've bought the Multiversity(in graphic novel form) on amazon. The shipping, however, is almost 50% of the book's cost and adds on a good $20. Buying regular printed books in comic stores(very far away from home) is even more expensive than having them shipped from amazon. I guess I just wish there are cheaper ways to buy printed comics for someone living far away from where they are produced(I live in New Zealand).
I'm still going to get omnibuses of stories I like, digital is pretty cool and I can read on a number of devices, but it's just different from the feel and experience of reading from a printed comic.