For the most part, the CX7 is a decent SUV. In particular, Mazda did an excellent job in the suspension tuning, and that results in a sharp handling crossover vehicle. It is no sports car by any stretch of the imagination, but the handling and vehicle dynamics are probably as good as a crossover vehicle can get.
The downfall of the car lies in a mismatch between the DISI 2.3L turbo engine and the vehicle's heavy chassis. While the 2.3L engine is a gem of an engine that produces massive torque and lots of power, it does so only when it is under boost (ie. the turbo kicking it). When dropped into the CX7's heavy body, the engine has to work extra hard and stay in boost quite often. This in turn results in poor fuel economy.
In magazine comparisons, C&D (and quite possibly MT as well) rated the current gen Nissan Murano higher than the CX7. The Murano has a more polarizing look, and you may not be used to the operations of its CVT transmission. However, I'd quite agree that the Murano is a "better" vehicle than the CX7 with its combination of awesome award-winning VQ engine, the smooth CVT operation (once you get used to how it works), and the overall higher refinement.
Last but not least, a $4000 discount for an old 2007 CX7 with 35k km on the clock is nothing short of a complete ripoff. Steer clear of that "deal".
Rav4 is actually quite efficient in the sense that it matches the speed of X3 and it has the best fuel econ in its class! It's VERY roomy and not bad looking, what a family suv should be...haha