About 3 years ago, I explored the idea of getting 2 Adventures AND a Getaway and decided to start with the Adventure, with the sail kit (not the Island version - the Island was announced shortly after).
Being a sailor and prior owner of a Hobie 16, 18sx, windsurfer, and big boat charterer, I still would like to have a Getaway (or other HobieCat, or Island) someday, when I have more time to enjoy both. The reality is that I am so satisfied with my Adventure that I am not in a hurry to get a cat. As mentioned by the skymax's previous post, kayaks are so easy to transport, launch, and operate solo (since I like to get out more often than my wife, this comes in handy). Here are a few other things you might want to consider:
How much time to you have to get out on the water? If you have the option of getting out for frequent short trips, then I would favor the kayaks. I live in an area with several lakes and rivers, affording me opportunities to frequently squeeze in a quick "peddle". This has been the greatest advantage of the kayak over a sail boat. I have used my kayak once or twice a week 9 months a year in a climate that has a rainy and cool winter. Far more use than I ever got out of any of my sail boats.
How steady is the wind where you live? You can always enjoy the kayak, wind or not. You never need to worry about with the AI. If I lived in a temperate climate, with steady wind, and easy launch locations, and a reliable crew, I might favor a GetAway.
Do you have narrow waterways with abundant wildlife? If you do, an Adventure will give you access to places you will never see with any type of a sailboat.
Do you want to sail together, or carry extra passengers on the same boat? Obviously this favors the Getaway. This is something I considered and would definately like to have, however, this requirement is too infrequent for me to sacrifice the other advantages of the Adventure.
I hope these questions/comments help you decide what is best for you. Either way, you will have a great time and won't regret getting a Hobie. Great products and support. I tried another brand of sailboat at one time and regretted it.