[Pills]

My main reason for gps speedo was the space saved by the gauge being a little over 1 inch deep behind the dash. This allowed me a lot more flexibility in my dash layout, and I was able to position my gauges the way I liked without interference from my heater/demister etc. My other issue was that with most other gauges, I was not able to find a speedo cable converter to fit my gearbox. I did not want to go down the path of an electronic wheel pick up.
As far as functionality, the only topography I have had problems with so far, have been tunnels.
The gps antenna is the size of a 20c coin roughly and about 1.5 cm thick. Has a good strong magnetic base and I have simply placed it on the windscreen pillar under the dash. You can conceal it under the dash on any metalic surface quite easily.
The quad gauge is ok. I preffer the look of the individual gauges, but if space or layout was an issue, then I would use the quad rather than do without a reading.