After forty years of doing this for a living, I can give you the absolute definitive answer.

(1) Take up beer drinking as a hobby.

(2) Visit every bar within a ten-mile radius of your lab. Twice.

(3) Take a tape measure and make careful note of the more comfortable dimensions.

It is extremely important to be able to lean your forearms both on your favorite neighborhood bar and on your darkroom sink rail. For every hour you spend in the studio or on location, you will spend a working day in the dark.