Side by side, Garmin’s new Edge 520 and Polar’s new M450 GPS computers are similar in size and shape, but quite different in price and feature sets. Which one is best for you depends on your budget and what you intend to do with the little handlebar-mounted machine.
The M450 is about half the price of the 520 – and has about half the features of the Garmin unit. While the 520 can connect to third-party peripherals like heart-rate monitors or power meters on ANT+ or Bluetooth, the M450 is Bluetooth only. The 520 has basic mapping and can give you turn-by-turn directions if you load in a route; the M450 can only point in the general direction of your starting point and its distance away.
But for some riders, more may not be better. If you just want a reliable GPS computer that can record your route along with all your vital metrics like distance, speed, heart rate, power, time, and so on, then the M450 does a good job of catching all this data.
How they are similar
Both units measure and/or capture most of the same data, including distance, speed, elevation and the standard variations thereof like average, maximum and total. Both have layouts that can be configured by number of fields per screen, and what information goes on that screen.
Both units can pair wirelessly with heart-rate monitors, cadence sensors, power meters and smartphones.
How they are different
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