Gyro Express is a pretty decent hole-in-the-wall lunch place. Its always packed, which is easy to accomplish with only a total of 5-6 tables. The style is very much fast food-like: its made very quickly, kind of greasy and it has a small menu of all the classic Greek favorites which get ordered, paid and picked up from the counter.
Now I can't say that everything tastes super fresh and made to order like some of the Valley favorites (Haji Baba). However, I doubt that's what Gyro Express is all about. For what they try to be (a fast, tasty and affordable Greek place), Gyro Express really hits the spot. Their classic gyro is decently sized, the meat is delicious and the sauce (and added hot sauce) make it the perfect combo. Their Greek fries (aka french fries with feta, lime juice and some parsley) are freaking phenomenal. The food wait time is minimal and the food comes out exactly the same every single time, which is great when you need some quick and tasty lunch food you can depend on.
Get extra napkins. You'll need it unless you want to end up with sauce everywhere.