It seems like printing to your DropBox folder would be the most versitile as DB is supported by a lit of apps on the iPad. Do any of the apps mentioned better dropbox?
Dropbox would have the benefit of not needing to have your iPad around when you print to it.
Two best options (in my opinion, in no particular order):
1. Save PDF to Evernote on your desktop, then open it using Evernote's iOS app--both are free (create a Notebook called "iPad docs," then put things there for quick access).
2. Save PDF to Dropbox from your desktop, then open it in the Dropbox iOS app--depending on the size of your Dropbox account, price runs from free to $$ (create a folder called "iPad docs" for quick access).
Depending on the item/purpose, I use both. They auto-sync outside the local network, items load fast, accessing documents is easy, and they're über-reliable. Win/win all the way around.