RCaillout3 has my vote. For the type of flying model pilots do the difference in induced drag between flat , rounded, or sharp tips is just plain insignificant. Full scale designers are concerned with range which is where small drag reductions become important. There have been many special tip shapes tried, the most prevalent at the moment seem to be the Hoerner used on some production light aircraft, and the "winglets" used on commercial airliners. If I remember correctly, the Rutan round the world airplane had the winglets. On takeoff for the record flight, one tip was damaged and the winglet came off. It made it around the world anyway.

If the question is just for sake of argument, though the squared off tip may restrict the flow of air bottom to top thus reducing "induced" drag it causes turbulent flow that represents energy loss adding to "form"drag, so the overall drag is likely the same or maybe a little higher. The only way to know for sure would be to run comparative tests under controlled conditions (in a wind tunnel maybe) and measure the difference.

On the typical R/C model if you are serious about drag reduction the first move would be get rid of the nose gear.