Anything with a USB port should work fine. I've charged my watch with my laptop, the usb port in my car, a battery powerbank, and a usb wall charger. All worked fine.
Garmin recommend charging their products using your computer USB. Some wall and car chargers apply too much amps to the device. Yes they charge faster with higher amps but it may be shortening the battery lifespan
I am unsure of how true the above is but to be on the safe side I simply use my computer to charge all my Garmin products....
That is wrong. A charger will never "apply" a higher current (A) than the connected charging unit use. It is the same for a light bulb that you attach to your wall socket, the voltage will be the same regardless but the current depends on how much power the light bulb uses.
It is true that a device may charge faster with a charger that has more power (higher current) but only if the device charging unit is built to use the power.
The reason why a lot of companies recommend that you only use the supplied charger, or a computer, is that there are a lot of cheap unreliable chargers that can case fire due to overheating (not the charging device but rather the charger). There is even cheap piece of plastic that in cases has an output voltage higher than the USB standard of 5V which may harm your device and cause over heating.
Buy one from a trusted and reliable manufacturer and you will be fine. It doesn't matter if it is a Samsung, Apple, Garmin or Motorola or if it is 1.5A, 2A or 2.5A they will work just fine with your Garmin watch.
