Speedo gear or Elect. Speed Sensor Recalibrator?

What would be better for fixing the speedometer after bigger tires? I have seen where people use different tooth'd gears, but then i found this:
http://www.jeepinoutfitters.com/scripts/prodView.asp?idproduct=946
It talks about stuff like engine performance and tranny shift points. is this worth it?
:thumbup: ?

the electric module does the EXACT SAME THING as the different toothed gear, it changes what speed the vehicle thinks you are going (usually to the correct speed). the ONLY difference is in how its done, and if you change gearing or tire size you don't need to buy a new speedo gear. for 150 bucks more than a speedo gear, i would shy away from it.

Thats what i kind of figured...since the gear is what collects the data from the actual driveshaft to begin with.
:shocked:

Yep. Changing the gear is easy and cheap. I see no reason to spend the money on one of the electronic doo-hickeys.