1/48's !! The size, proportion, ease of transformation, landing gear!! Love it, my only complaint ever were the hands they came with, but thats an easy fix. I would voted for the 1/60 VF-0 Phoenix, but with the QC issues making it a train wreck and a risk for the money I had to by pass it, still one of my favorite designs though.
Also as noted by those who mentioned the VF-0 does transform like it does in the OVA, with the issues Yamato had with the arms, can you imagine them using those slim swing bars for the legs, could have been the 1/72 VF-11 all over again!!