as long as its not hot. anything over room temperature WILL fry your filters, you may not have a choice because you need to turn up both hot and cold to achieve the best pressure in which case i would buy a booster pump.
more water is not made, just less bad water is rejected. here is why... when you heat up the water, you will heat up the filters and membranes, causing them to expand which means the holes in them get bigger. depending on your temperature you may increase a 1 micron filter to 2 or 3 microns. same goes for the RO membrane, your just increasing the size. in turn you will be reducing the rejection rate of the filter. the water will come out faster only because its path is less restrictive now. therefore, the quality of your filtered water will suffer. you will in fact get the best filtering out of colder water.