re: 0% financing on car--is there a catch?

Financing shouldn't matter in the price. You should have fully negotiated the price prior to discussing financing. There are often rebates/cash in lieu of the 0%, but not base price.

X-Plan is Ford's program for suppliers/affiliates. Similar to the GM Supplier Discount, Hyundai Inner Circle, Nissan VPP, etc. It's just a set price with no haggling or extra fees. It can sometimes be beat depending on model. It's often worth the trouble simply to avoid dealing with dealer. You walk in, give them number, and price is set. It's often not a bad price. X-Plan and GM can often be beat, Nissan/Infiniti, Hyundai, MB and some others are really good prices.