Something that comes up every once and a while is the effect of temperature and pressure to the output of the ro membrane.
Read that the GPD rating is based with the supply water at 77°C and 65 (or 60) psi and I've been reguratating a 1.6% drop in output per °F (from Aquasafe).
What started to wonder was how linear the drop with temperature was and found a couple of tables in this link:
http://www.freedrinkingwater.com/infocenter.htm
As we all know the Internet is nothing but fact, but seems the last table is close for my unit (it doesn't get anywhere near the 100gpd rating).