I need 1 day's slice of data from these feeds, but don't actually need the subscription. Anyone willing to be my friend here? I'm going to go begging as an academic, but perhaps some of you can lend a hand. Format should just be a raw binary dump of the UDP datagrams on a given day in their original format with the original timestamps. The next best thing I can do is pimp Genesis' feed, but 1) I know they drop packets sometimes, and 2) they don't give the original exchange timestamps to the highest precision possible.
Not sure if this is what you are looking for but there are/were some sample ITCH files at Nasdaq: ftp://emi.nasdaq.com Look under the cunningly named ITCH folder.