If you start to look over the failures from 06 thru 08, they have mounted up.... Mast, mast receiver, rudder pin, rudder change out, rudder lift kit, storage seal, fin replacments, aka release pins....I don't want to be negtive but 50% of the post on this site are about failures or updates... but reliablity is in question.
As compared with my other half who is still paddling a 700$ model in a stright line. She is starting with I told you so. As the loading weight,time,cost,refits are starting to mount up. I got a lot of money and time into this hobby vs time on the water. ...I do find that the older kayak I have is faster to get in /out of the water. But far less fun.
In 2010 I will try one more model with expectation of no upgrades or failures for five years.
Kepra, your concern is understandable, but the forum is the exact place to bring out problems and pose solutions. So naturally, one hears about problems. But if I have a problem that doesn't mean you have a bad boat. If it makes you feel any better, I've had 2 AIs and no problems -- no rudder problems, no mast problems, no sail problems. This may sound like the exception, but I'm guessing there are a legion of folks out there in the same situation. It wouldn't be very productive if we were chiming in about our lack of issues.
The great thing about this is I see some excellent solutions in case I ever do have a problem. As for changes and upgrades, all of us would be driving boats like your wife's $700 straight line model if Hobie weren't improving their products with changes all the time. In fact, Hobie's first AI's were the direct beneficiaries of over 40 significant functional improvements in the Hobie Mirage kayaks since I started using them over 8 years ago. In another 5 years, I suspect we're going to see lots more improvements. This is a great thing if we hope to have better products.
My wife has been telling me that "she told me so" ever since we got married. I'm pleased to be able to make her feel good about her great foresight and knowledge and intend to keep giving her that satisfaction! In fact, I frequently give myself a pat on the back for marrying such an insightful woman. If you're boat is giving you pleasure and she's also satisfied then all is well -- enjoy your AI. Obviously what's fun for you isn't necessarily fun for her. But don't expect 5 years with no problems or no changes!