At that time of the morning, you're going to get snarled up in
central Hemel Hempstead to at least some extent. The two
biggest variables in your equation 1) are how quickly can you
get from your house to either the M1 or the A41 and 2) how long
from either route before you hit the morning rush hour tailback.

Good luck either way. I don't work any more so I don't have these
problems. Mind you, tomorrow a friend and I are going to Wells,
Castle Combe and Cricklade and I have to work out the best route
there and back via Dulwich!