The AirSport VFR is built to exactly the same standard of quality as our other models but at a budget price. Our competitors make fine equipment, and strictly as alerters they are all good investments. But they are wired to the altitude encoder. Other alerters don't monitor health or status of the transponder. Your transponder signal is what the controller sees, you should know what your equipment is actually reporting.
Most pilots place their Alerter on the glareshield.
Depending on the aircraft, you may prefer to locate it under the instrument panel or elsewhere. Since it's portable, pilots find a variety of locations. It comes with Velcro strong enough to hold during turbulence. Some AirSport Alerters have been permanently installed and FAA approved via 337s. The general answer is about 8 hours, enough for an average day's flying.