Wildergeek, if you do decide on a hammock, you can always store your panniers beneath you and under your tarp. (I'm assuming you will be using a secondary tarp.) But again, I'm like staehpj1, I rarely take my panniers off the bike at night. Hammockforums.net is a great place to hang out (pardon the pun) and I'm sure you can glean much information there. Also if you do a search on this forum, you will find this topic has come been spoken about in depth in the past.