I finally got a chance to follow-up on a chow-potential sighting I made earlier this year (errr, I should now say last year). The Manfredi Depot--which is a gas station with a large mini-mart--is at 6920 Dunsmuir Avenue, just off I-5 at the southernmost of Dunsmuir's three exits.
As luck would have it, I passed through on a Friday, the one day of the week they set up an outdoor grill (supposedly all year too, no matter the weather). From the grill, they serve whole beef tri-tip ($14), pork tri-tip ($7), half and quartered chickens (about $5 and $3, respectively) and a few other items that I have now forgotten (baby back ribs maybe).
The beef tri tip is also served on a sandwich ($5), which is what I tried. The sandwiches are served on house-made buns (white, wheat, or sour) that are very soft and fairly tasty (we're not talking Acme here, folks, but better than most sandwich chains or supermarkets will sell you). The thin slices of meat were about medium well and had a great smokey BBQ flavor around the outside edge. The only problem is, and I didn't notice this until I was about 15 miles up the highway, that the sandwich is a sort of sub (or should I say hero, or hoagie, or... :) with shredded iceburg lettuce, tomato, pickles, peppers, mayo, and mustard. While there was nothing offensive about any of the ingredients, it reminded me too much of Subway/Togos (though far better, mind you) and wasn't the sandwich I was hoping for. But the meat and bread are good, so if you find yourself in that area on a Friday I think it's worth stopping and asking if you can get a meat-only, medium rare sandwich.
Try as I might, I couldn't get my companion to try one of the other Friday grill items or their other specialty: house-smoked turkey. She instead opted for a sandwich made with some kind of packaged low-sodium, low-fat something or other turkey breast. Other than the meat, the sandwich was identical to mine.
There's not much of anywhere to eat your sandwich at Manfredi's, unless you count sitting in your car in an unattractive and mostly dirt lot. We ended up eating our sandwiches on a frozen park bench in downtown Mount Shasta City.