Ouch! I just did a map check and it looks like Tustin is a suburb of LA, thus you take I-10 the whole way. Other than the sheer pain of having that drive take so much longer, I don't understand how you didn't get rear-ended the whole way, considering the speed limit is 70 in CA and 75 in AZ. Doing 15 to 22mph under the limit is a pretty big speed difference! Speed differential is what causes wrecks on the highway. That's the approach velocity equivilent of going 97 miles per hour when the rest of traffic is doing 75. You are a brave individual!