i have one wooden bowl set up with Proraso green from the plastic tub
i also have a ceramic bowl with the same , and a pewter bowl with taylor of old in it ..
i generally fill the bowls to the top with hot water while im in the shower , and then fill the sink with hot water with just enough to almost get into the bowl ... ive noticed only the ceramic bowl holds it heat but either way the hot water keeps the soaps soft for me and allows me to get a good lather with just the water in the brush ...
on a side note i used cold water last night and it really brought out the soothing feeling of the Proraso , prob didnt help with the beard though ..lol