Hi dplanet. I own an Alpacka, the dory (now superceded by the Fjord Explorer). It would do the crossing easily, it's only 200 odd metres. The other consideration is that as you have your own water transport, you can cross wherever you like, which may narrow down the required crossing length. The other folks' reasons for not carrying it are sensible though... if you already own a packraft, I'd plan a different sort of trip, try 40% walk and 60% raft, by distance. Or at least throw in a packraft 'leg' - raft from Melaleuca to the Port Davey Track !
IMO sirius Tas's concerns are from not understanding the alpacka, which is in a different league to most peoples' raft or float tube experience. They are NOT primarily calm water fishing platforms, they are wilderness transport units which have been used in up to Class IV whitewater (sure as hell not by me though !).
Roman Dial's link below of walking and rafting in Patagonia and New Zealand have me AMPED for this kind of trip. I am considering saving hard for a second raft, probably a YukonYack with sprayskirt, for my +1 for trips.
Some of the PAckrafting forum folks seem to be from or travel to Tas so you may get an answer from them too.
Here are some fun packraft links for you and other readers:
rafting the Denison and Gordon Rivers, Tas:
http://www.alpackaraft.com/forums/viewt ... f=13&t=176Tassie:
http://www.alpackaraft.com/forums/viewt ... f=13&t=154http://mediafeliz.com/index.htmlhttp://www.aktrekking.com/beyondSpec/raft.html#alpackahttp://www.alpackaraft.com/forums/http://mulvanyadventures.blogspot.com/2 ... ition.htmlhttp://packrafting.blogspot.com/http://www.alpackaraft.com/forums/viewt ... 423&hilit=Jules