Well, Mazda's engines aren't really known as models of fuel efficiency. I don't think they're even as good as claimed, but that may be in part due to the way people would tend to drive a Mazda too.
If leasing, I would consider some other cars too. Not that I don't like the Mazda, because I really do especially in Wagon and Sport GFX Pkg configurations, but I think leasing is very interesting, as it can afford you the potential to really step up to more expensive cars because other factors are taken into consideration beyond price: leasing rates, behind the scenes manufacturer-to-dealer goodies, and especially residual values. A strong residual could nearly make a $30,000 car the same payment-wise as a $25,000 car. I may be stretching it a bit, but really has a profound effect. I'm sure leasing a MINI is comparatively low because of this, or a Jetta/Passat TDi Wagon, Accord V6, Acura TSX, or maybe even a Subaru Legacy. I don't know, but I suspect you can't base leasing on MSRP the way you do with financing.
Hey, what colour are you two after on the 6 anyhow?