I forgot, since Ford is still a partial owner of Mazda....you can still get S-Plan which I believe changes the price to around 3% over invoice + no admin fees.
Mazda USA - The Official U.S. Site for Mazda Cars, Crossover Vehicles, SUVs and Trucks
When you use a X/S-plan PIN, the dealer MUST show you the invoice and at the bottom it will show the X-Plan price and the Holdback cost. Make sure they show this to you.
Use the same link I provided earlier to obtain a PIN.
And good luck, both cars are great. AND TEST DRIVE THEM BOTH BEFORE YOU MAKE A DECISION. I hope to order a ST in November.