Disneyland route to South of Bullhead City route?

We usually vote for the shortest route (gas mileage, you know) - and once you get past the traffic, the I-40 route out of San Bernardino is the shortest and quickest, according to Google Maps. The run over the mountains to Victorville might be uncomfortable, depending on your rig. I'd probably go up to 40 thru Joshua Tree. Just a tad slower, but IMHO an easier drive. We usually start out in Palm Springs, and from there the run thru Desert Center to Bullhead is our choice.

al