Hey Gav ,
We've already talked about this (off air) but for the benifit of others that are intrested
I essentially have three packrafting pack systems that I use:
For longer walk in/out trips with white water (really wet conditions) I use a Pacific Outdoor Equipmnet Gobi 84L. It is huge and can fit all the gear (including Raft, helmet, paddle, pfd, throw rope etc) for long haul trips. Very serious pack with comfy and supportive harness (that can be removed). These packs are perfect for upside down portage attachment as show in Darrens pic. The down side of the Gobi is that they are not made anymore.....but, you may be able to get a secondhand one if you hunt and it is really worth the hunt. These are the bomb as far as packraft specific packs go, and at a tad over 2kg they are not too heavy considering they are super super tough and 100% waterproof.
https://www.mountainmailorder.co.za/ind ... uctId=1207. It is very important that a pack for whitewater does not absorb water, the extra weight of the water soaked into the pack can be very dangerous in a WW situation and a big pain in portages (extra kg's). The earlier quick release Alpacka Pack-attach system (with the quick release) is the best for ww, but again I don't think they make them anymore (I have got a several different attachment sytems but that is whole other thread...).
For trips where it is unlikley that the pack will get wet (ie flat water paddling only) I use my GoLite Pinnacle, the benifits of these are well documented on here, at 790g they are light, strong and comfy. Broken down Paddle sections fit really well in the side pockets. Don't use the Pinnacle for white water unless you stick it into a dry sack. I have a large Sea to Summit dry bag with the air purge valve that my Pinnacle fits neatly into.
For day trips or side trips I usually throw my day pack into a S2S drybag , they are the best dry bags I have owned and I have a range of sizes that I use, they attach nicely to the packrafts also as seen on my boat here.
http://www.youtube.com/watch?v=q8NOYXg5fxUSteve