First driving at night generally is a bad idea because of many large animals(cattle donkeys etc) on the road. Also drunks not limited to cars but large trucks. Driving during the day is easier on the nerves and you can see stuff.
As for San Quintin. It has gone from a sleepy little town (I first went there 36 years ago) to the largest agricultural area in Baja. It's a 15 mile garish strip mall with all of the problems of a big city and lots of single men with money to spend. I have never felt threatened there and I go through it a lot. Not as much as Tom but during the day it just feels safer to me. Just my dos centavos.
The road south of Puertocitos has great views of the Sea of Cortez but it can be a challenge after the rains. Having said that every time I go I see a family of Mexicans in a 64 ford wagon taking there time and making the trip. I like that road but Pam prefers going in through Catavina.
I dont think I'd get an argument here if I said Baja has changed and continues to change dramatically. The longer you wait to go the more it will look like an American Colony. The rest of you guys can weigh on that.
Just a word about Bay of LA. The road now is nicer than Mexico 1 and with that brings more traffic but I think its still worth going there. It doesnt take long and a side trip to Mission San Borjas is worth doing. Be sure to stop at The Ejido house (the local caretakers). They are lovely people and will give you a great tour of the restoration work and the history (they have no love for the Franciscans). They are very poor and a small donation is always welcomed and they do some nice hadicraft work too. Also Its not a bad place to camp or just to picnic. Its a fun rough road through some great scenery as well.
Bay of LA is very commercial now but you must go to the sea turtle sanctuary its fantastic. We camped near there in may of '05 and had a hump back singing to us all night long. These kinds of experiences really are life changing.
The fact of the matter is if you love Mexico and Mexicans Baja is heaven on earth. It is far and away my favorite destination and I've been going there starting with when my non spanish speaking but adventursome parents used to take me there back in the late '40s ('48 Pontiac) until now 50+ years and still passionate about the place. I've run on way too long but GO!!!!
Here are a couple of pix from that trip also.