Since it is your first time, and nearly half of your trip will be dedicated to Universal, I'd say you could skip the hoppers this one trip. As others have said, there is so much to see in each park you'll have a hard enough time fitting it all into one day, which is basically what will be allotted. If your teens tire of any park (probably not, but an if) you can always take the rest of the day to explore a resort or two, Downtown Disney, or the Boardwalk which doesn't require a ticket. The nearly $300 you'll save could already go to a downpayment on another trip with hoppers for after you learn what you like most at each park. I think you can also upgrade the tickets while you're at the parks if you do decide hopping would be best. It's a flat rate no matter how many days are left. Whatever you decide, I hope your family has loads of fun!