When i hear a length pronounced for a driver, i automatically picture it being the entire diameter of the driver and not just the cone, or the cone plus surrounds.
This means that the edge of the basket holding the cone and surrounds is also included in this measured length. In double checking the 6.25" drivers on my M60s, the cone plus surrounds is actually more like 6" with the basket edge taking up the last 0.25".
If none of this changes the fact that your Infinity drivers don't measure up to 6.5", then i would have to say that is false advertising, unless of course Infinity can define the length of their drivers in some other way (front to back perhaps?). But that would not make much sense.
