well, theres really no reason to go with a lower wintergrade oil. If your engine is like most sr's, its got enough miles on it where you can move up to a thicker viscosity oil to keep the oil film around your bearings lubed for reduced noise and longer life. which is definately a noteworthy tip if your running your engine at high RPM's more than the evreyday driver. but the bottom line is: it doesnt get cold enough in florida to worry about. stick with a 10W-30/40, IMO.