We will be starting our trip in San Fran and then driving down to Monterey and Carmel for a night or two. We then want to drive down to Santa Monica. We have done the Highway 1 trip down the coast before and do not want to do it on this trip. Is there a big time difference between Highway 101 and I5? We would like to stop and lunch somewhere or spend a couple of hours somewhere on the way down to break up the trip. We will have 2 teenage boys with us if that impacts the stop. Any suggestions? Thanks for any help.