[2point]

Annual Pass is $1119, so £860, which is roughly the cost of two 14 days tickets.

The benefits?

The biggest one is parking. At $25 a day that annual pass on 28 days could save you $700. Staying onsite - not so much of a saving as you get park parking for free and you have to pay for resort parking. I'd be booking offsite.

10% off most restaurants and 10% off most merchandise.

Note - you only need to buy one annual pass to get all the benefit (so may be cheaper to buy one annual pass and 2 14 day tickets)