Carolina's is one of the best Mexican food places in the west valley. The wait is long, sure, but if you call ahead of time and take it to go the wait is minuscule.
I normally get the #9 which has two tacos with rice and beans. The flavor of the beans is amazing plus they are rich and creamy.
The price is super cheap. A family of 3-4 can eat here for $25 and under.
I would recommend staying away from eating inside the place because it is a bit hectic and not always clean-- given that they are busy.