Recently acquired a used Koaloha concert and want to experiment with strings. have some Ko'Olau strings coming and wanted to order some Worth strings as well but not sure of the gauge; either lights or mediums. Any concerns about putting medium gauge strings on a concert uke given that they don't have truss rods? what's the standard usually? do most people use lights? with my other cheaper ukes i just always used Aquilas in the standard concert set and they didnt have any specific gauge. Sorry for the newb question!