I'd get the Tomcat. Even the cheaper line of Aires is better than a lot of other IK's. I wouldn't get hung up on the Dropstitch floor, I've had a Jumbo Canyon IK with a DS floor and didn't think it added much rigidity. Tribs are plenty stiff with a good floor design/ transition that can easily be serviced, and the Aire warranty is hard to beat.
Wishing I was on the river instead of surfing the web...