$1450 for that boat is a pretty good deal- retail is $2100 AIRE | 12.0 SB Raft Tributary Series
. My buddy bought a barely used 14' Tributary for an oar boat for $1600 last year and took it down the Main Salmon- he had no complaints about handling or durability. As far as I can see, they're pretty well built for the price. The knocks would be that the valves are lesser quality than the regular Aire boats, and the PVC is a little lighter wieght than the higher-end models. But they're 2/3 the price. There are a few other variations in dimensions (tube diameter, bow/sern rise, etc), so keep those in mind when comparing to the other Aires- especially the Puma. I'm an Aire fan, so my opinion is that Aire boats in general are pretty well built and reasonably priced regardless. With the bladder system, lighter external fabric isn't as big of an issue as it would be for a a light-fabric boat that relies on external fabric for air pressure integrity.
I will say this: if you're planning on putting in more than 30 days a year on rocky sections of river, and you want to buy the last raft you'll need for 10 years, then it will probably be worth investing in a higher end boat (of any manufacturer). But, if you're primarily a kayaker who's looking for a boat that you can use for a couple of multi-nighters, overnights and and a few daytrip floats; then I think the Trib is fine.