If you eventually plan to make it to both islands I would go FIRST to whichever island is LEAST attractive to you. Maui is developed much like the style of southern California (where I'm from), and we saw MANY people at all the sights and hiking trails (including the road to Hana). Kauai is less developed (although there IS a Starbuck's or two), and we have been to many beaches and on many hikes where we saw no or few people. Some people call that "Lonely" or "Boring"....just depends on what you like and what you want out of your vacation. Personally, after 3 trips to Kauai, I was very disappointed in Maui....but I do know many people love the place. Don't get me wrong, I did have a good time in Maui and saw some beautiful sights (the wild shore past Kapalua and the Iao Needle valley). Maui just didn't somehow feel as "Magical" as Kauai. I'm sure it's a very personal thing. My husband felt exactly the same way. I think if I went to Maui first it wouldn't have been such a let-down. And then I could've gone on to the more spectacularly beautiful Kauai....

just got back from Maui..i would choose Maui. i like Kauai also.