One of the major advantages model r/c racing boats have over full size yachts is the ability to quickly change an entire rig and sails. Where it can take days to restep a rig for a major offshore yacht, the rig on an r/c raceboat can be changed in under five minutes (and in the case of a swing rig, under a minute). Further, since the sails on an r/c boat are permanently attached to the rig, they never suffer the distortions and failures that sails that are rolled, reefed or folded undergo.
This ability to quickly change rigs also means that sail shapes, cuts and materials can be matched to a wide variety of wind conditons. Further, the rig materials and design can also vary. For example, the stiffness of carbon fiber mast tubes and booms can be varied as wind increase or decrease. In the Marblehead class it is not uncommon to see the top sailors have six or more rig and sail combinations. Even in the IOM class where you are limited to three rigs many sailors have two or three “A” rigs made out of different weight materials with different cuts to choose from prior to the start of a regatta.
Another major advantage model race boats have over large yachts is because the materials used in r/c sails are often much lighter in weight than big boat sails the sails can be glued or taped together and therefore have perfectly smooth surfaces. In the fastest of r/c racing sails even the sail numbers are painted or magic marked on so as not to interefere with flow. In fact, in many sails there is zero sticthing whatsoever.
Finally, because the amount of material involved in a model boat’s sails is so much less than that of a big boat, it is very easy to afford multiple sets of sails. The most expensive custom made sails are still priced around $100 (and some sailmakers charge much less)and the cost of materials to make sails at home can be under $20.