Reviewing several of the 20 amp 12 wire VS 15 amp 14 wire comments I did a voltage drop check in my own house on the kitchen circuits and was amazed at the drop on them! They are wired in 12 ga wire. I became aware of the basic rules of wiring, longer runs equal voltage drop and it isn't 20 amps vs 15 amps its length vs load expected at the far end. Ya might need to run 12 to over come voltage drop on a 15 amp circuit or 10 on a 20 amp circuit. Since then I've re-thought my thinking on wiring circuits and upsize sometimes just a home run to cut voltage drop. May not be the cheapest route but too many "electricians" don't get past the wire size vs breaker size point of learning