My 2 cents:
I have a CR first gen compressor and upgraded to the 2nd gen blower box last year. The air has always been cold, mostly, but as noted above, a second condenser really helps when in traffic and/or moving slow. It just provides more capacity for extreme conditions.
The problem that I have noted many times is simply the volume of air that is turned over by the overall system. The CR blower is capable of moving a generous amount of air, but I have always been convinced that the stock blend valves and the stock 60mm plumbing were the restrictions. Turns out, at least in my case, that this is true. I went on a mission to change the plumbing from 60 mm to 75 mm both for the INPUT side of the CR unit (which I believe is the overall bottleneck of the system) and the output side of the CR blower and blend valves.
Results shown below and it has been well worth the effort. The volume of cold air that is now moved through the system is dramatically improved over the stock setup. Please keep in mind that I don't have heat exchangers or heat from anywhere, but I do have some small PTC heaters hidden inside the, still factory, plumbing just before the defrost/windshield inlet port. This works really well, but it is only useable for defrost and is not nearly enough to "heat" the cabin.
The blend valves are controlled by some switches in the stock location (sliders and bowden tubes are history) and by a really simple Arduino program/setup (credit to Julian for the idea/inspiration). Their function is 1) Fan 0~3 speeds), 2) A/C on/off, 3) Footwell/dash OR Defrost, and 4) Defrost (PTCs) on/off.
I still plan to coat the windows with a film, but it's lower down the list of priorities at the moment. I still want to do some faceplate updates and I am working on a valve to include fresh air ahead of the CR Blower (currently 10% blocked). I know this will move even more air when complete and also add a fresh air only option.
