I've demo'd iBank. It's fine as a banking tool for basic checking, credit cards, and such (much easier than Quicken, which is fine if you have a fairly complicated financial situation).
The drawback is that iBank's budgeting feature is very under-developed and not very useful for real-time (or semi real time) tracking of budget categories.
I've yet to find any financial software that easily and conveniently lets you intereface with your bank to keep accounts current, set up a monthly budget, track expenses against that budget, and let you go mobile in iPhone and do all that real-time on the go (meaning over-the-air sync'g via DropBox or something else).
Seems such an obvious feature set for basic financial planning, but each software package I've looked at (Quicken, iBank, YNAB, Mint, etc.) addresses one or two of those features and ignores the others.
ymmv.