Welcome to the “hidden” majority. You follow directions and take proper care, your Karma should last a long time. By far that is the case for the vast majority of owners. What you see on this forum is almost exclusively complaints and problems. Anything electronic can fail, some Karmas do so, others are mistreated by folks who buy, run out and fly out of box, as is possible, for the first time and anything that happens then or afterwards is the fault of Karma.
Karma was not made for FPV flying out of sight. It was made for a good picture taking platform for the GoPro within reasonable limits. It does that quite well. Yes GoPro indicates a maximum range etc. All that depends on conditions. Karma is WiFi based, both control and video/data. Any place you go in an urban environment is flooded with WiFi. (In my Houston townhouse my scanner can see over 20 WiFi signals, some very strong and probably on illegal boosters.) It absolutely causes problems. Remember any RC device that does not require a license for the radio interface is using a spectrum of WiFi, as do many household wireless devices. That includes every single RC device available online, hobby shops etc. If the proper frequencies are not used the seller of the devices is severely fined by the FCC. Hobby King and others have found that out. I have quads I built that use ham radio band VHF and UHF frequencies, and I have a ham radio license.
If interested in improving radio performance of Karma do not buy any device to increase power level at the controller. That is a one direction fix and is also illegal. All this wifi use is limited to very low power levels. All you can do is put bigger patch antennas, or similar, on the controller. This way there is gain on both the transmitted and received signals. That does help. Gain is measured in db and a 3 db gain doubles the effective signal power.
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