For us it doesn't work and here is why:
1. Peak Surcharge periods - Disney adds an 'upcharge/surcharge' of 4.00/adult and 2.00/child for buffet meals during peak seasons for buffets. We go for almost 2 weeks each July, and most if not all of our trips are during this period, so if doing TIW, we would have an additional cost to meals. Not worth it to us. Please don't tell us to not attend buffet meals as we have kids, and they are worth it for us to get autographs and cool down from heat!
2. Don't drink alcohol - We don't drink alcohol at all.
3. Mandatory tip - Not going to debate or discuss as per tipping guidelines on these boards, but DH hates this, so no go.
4. Increased cost of card - Card has gone up and up the past few years, and I'm sure, it will go up even more too.
5. Small kids - DP is more of a value to us with small children. We have run numbers a million times before each and every trip (hubby is a banker and I'm a highly detailed-oriented planner), and DP is still cheaper for us each and every time - whether it's DP or DxDP, plans are still cheaper due to our family make-up at this time in our lives.
We just ran numbers for upcoming trip next month, and we are just about even for DP and TIW, but then we have to add in cost of card, and that puts us over. Then we have to look at July, and again, we are in 'upcharge/surcharge' territory for whole trip, so TIW is more expensive for us for both of these trips.
We have done DDE before when it was cheaper card and no manadatory tip, and that is what we like. Can't seem to make it work for us at this stage...
Just a different perspective, Tiger