For $15 per day or $24 multi-day you'll be able to get speedy, in-park and site-to-site transportation. I wonder if it's worth it? We rarely go from park to park. Rather it's typically park, resort and rest then park. I'll tell you want I would pay for is full day, unlimited FP+.
http://www.wdwmagic.com/transportati...ket-option.htm