The 2008 should have the "v2" drums and cables. You can tell if the drums look like "Mickey Mouse" ears vs the older drums. The "v2" masts and sprockets arrived in 2009 -- any Drive can be upgraded with this improvement for about $50. You can always upgrade if and when you have a problem with the original parts sometime down the line.
Accessories I would recommend with your $400 savings are (optional) large rudder for much better directional control, plug in cart for easy transport to and from the water, and ST or ST Turbo fins for better pedaling efficiency.
Seating comfort is a personal matter. The 2010 seats have a higher back on the hardshell kayaks, but I don't know if they changed the inflatable seats or not (slightly different seat construction). If so, it doesn't appear to show in the catalog.
The bags have not have rave reviews for toughness, at least with the airline baggage handlers. I would think they would do OK with wind buffeting though, especially with a leading edge slip cover (any auto upholstery shop could make one for you).