Am off for a fortnight to central America with some independent travel and one week based in one place.  My ancient Karrimor Jaguar 65 is at death's door and I'm thinking maybe a travel pack is the way to go.  The Osprey range look fab and reasonable value for what they are, but have just discovered this one, which must be discontinued:

http://www.sierratradingpost.com/p/311,83071_Osprey-Departure-60-Travel-Backpack-Convertible-.html

Absolute bargain at £73....anyone any experience/advice with these things?  A friend has a Black Wolf one from Oz which is greta but with wheels is SO heavy, so thinking no wheels is better, but the above one doesn't seem to offer the zip away harness....too many to choose from...arrgh.