LeBron,
What "The Dog"
should have told you if he knew what he was talking about has nothing to do with stickers.
Every Hobie has a serial # inscribed in the hull that includes the manufactured date. The last 4 digits tell the month in letters (A through L), year made and year model. For example, #....L506 means the boat was built in December (
L) of 200
5 and is a 20
06 model. The serial numbers are inscribed on the aft section of all Hobie hulls off to one side.
The Tandems went through a major hull change sometime around '02 or '03 when the capacity was increased by 100#. It also picked up a sail mast receiver several years ago (hole behind the front seat) for the addition of a sail. No other major changes that I am aware of. There have some minor changes in non-hull areas (removable seats; two 8" hatches added this year) but these are of little consequence if you can find a Tandem in good condition.
The Outfitter is pretty new and I doubt that you'd find a used one.
The drives have evolved in small ways in order to lose weight (about 1# or so), but their design has not changed much. My 6 year old drives work as well as my new one. Some people even prefer the old style drives (recognized by their aluminum frame, stainless sprockets). They're all rebuildable, I think.. Condition is by far your biggest inspection point (nothing loose, squeaky, visibly worn, etc. Any drive should work in any hull, old or new.