Might help more if you posted the area you wish to go to.
The AI vs Non AI issue is a very debatable issue among travelers. WE frequently do AI and find we get our monies worth and more. We also find it makes our vacation more relaxing as no real decision making. We do not hesitate to even go out to an offsite restaurant a few times during our stay if we so desire or want to check out a new place etc. Some AI's include much more than just your meals and drinks, like stocked kitchens, 24 hour room service, valet parking, and the list goes on. The higher priced ones are generally much better for the most part. You get what you pay for I guess.
We find unless we really scrimped on eating and drinking we either end up breaking even or a tad ahead with AI. Then again depends on where you are going, taxi rates and such.
Might be able to help you more if you give a bit more info, like where you were thinking of going? Where you were thinking of staying etc? Good luck!