Maybe I'm a little late on this, but my "go to" spots have been:
- For non-directed smog tests, Save Auto. It's about a mile from Porsche of San Diego, and super cheap. Not quite North County. I live off Camino del Norte, and it's a bit of a drive south for me. Go to their website, print the coupon for an $11.25 smog check + $8.25 certificate == $20 out the door.
http://saveautorepairsmog.com/- For directed smog tests (STAR or test-only stations), I use Penasquitos Auto Repair. They get pretty good ratings on Yelp for overall service, and they've always been really fast to do my smog checks on my Evo, which always end up being directed tests. I guess they don't trust the cheapo stations to know what a modified Evo looks like.
If you go there, go to the website and print out their $10 off coupon and take it with you.
http://www.penasquitosautorepair.com/