Long runs has nothing to do with the decision of the amount or type of shield requiered (well, even despite the fact that the longer the run the greater the risk to be exposed to potential interference ) but rather the amount of interference that the cable will be exposed to. RG-6/U is more than enough for most aplications. Also not because someone is 6 feet tall will necessarilly beat me playing basketball (specially because I throw almost 100% perfectly out of the 3 line point even when blind folded or at least I used to , lol) therefore not because the cable is Quad shielded it will better than any other RG-6/U outhere at rejecting interference. There are broadcasting quality RG-6/U cables that their shield is more braided or better that another low quality quad shield coaxial.

Long runs affect signal strength and also the Voltage at the end of the line. In those cases lower losses cables with all cupper center conductor ar better. I do not even think they manufacture long runs of flat cable but as always I could be wrong.