Air Compressor For Sale

Harbor Freight has 2 models of air
compressors on sale. One is a 3hp model,21 gal tank @120 volt, 125 Psi.
The other model is the same except it’s 230 volt, 115 Psi. Which is the most efficient model to purchase?
I plan to use it for spray painting cars and trucks.
Thanks for your help. George