Scrim
You could also play around with the figures on RO-Man site to get some idea of what you can achieve (product water wise anyway) buy entering different water input temps, different RO units, different input TDS readings, different input PSI, etc
Click on Ro-MANs website/ support/ system performance
I would post the link but ro-mans site wont allow me to copy the shortcut
I also looked at this before posting a thread Called "Optimun working temp"
http://www.cleanitup.co.uk/smf/index.php?topic=18794.0Because as paul posted you could warm the water first to produce more , I was thinking along the lines of heating it feed first to get my 100gpd RO to produce more than stated
Chris