As mentioned in the first post on this thread, I am concentrating on modules that are 2' x 6' as these will fit into my minivan. While a 2 x 4 module would be lighter it does not 'pack' as well as a 2' x 6' module. Meaning I get better utilization of space in the minivan with 2' X 6' modules. In addition the longer modules mean less transition tracks between modules. So while the 2' x 6' modules are heavier there are some important trade offs that have to be considered. That being said, the 2' x 6' modules could be carried by one person but because of their length they can become unwieldy for one person. We generally clamp two modules together so two persons are still used to carry them. Still there are ways to make them lighter. I avoid use of the 2" styrofoam preferring to use 1/4" luan underlayment. Several reasons for this and one is the loss of 2" of clamping area on the end boards for clamping the modules together. I want that clamp to be as high up and as close to the track as possible.