Pretty much what everyone else said is all you need to know. The biggest issue is definitely the cams, as they are draw length specific. If you can find the ones you need for a reasonable price, and find a shop to put them on for you, it's not a bad deal. Although I think hch is right, you can probably find an 06 with adjustable modules for less money if you keep your eyes peeled. This is the time of year when bows start to magically appear in the Classifieds and places like ebay.
I own and am currently shooting an 05 Allegiance and I love it. Couldn't be happier with the bow, the way it shoots, or its performance at the range or in the field. I haven't had a single problem with it and look forward to shooting this bow for as long as I can manage to pull it back.
Of course I'm in the market for a new bow this year, so we'll see where I end up. Gonna shoot a whole bunch of them and see which I like best, then make the call from there.