I used the IRC GP 110 when I did this trip on a KLR, worked great, down and back. I also have the GPS tracks if you want 'em, send me a PM. There's a guy that offers Garmin maps of Baja, google him.
BTW: we crossed at Mexicali, then to San Felipe and so on. Spent lots of time on the Baja XXX courses.
I have a neighbor who used to be the State Dept Station Chief in Hermosillo and Guadalahara. She advised us to get up really early on the day we are going to cross and get at least 150 miles south of the border before noon. I guess the drug war doesn't get going until after noon.
Once we got south of San Felipe, we never had any issues.
Have fun.