Frontera Grill is a highly regarded destination for Mexican cuisine, commended by about 75% of reviews for its vibrant and bold flavors. The quality of food is frequently described as "outstanding," "delicious," and "fresh," with dishes like ceviche, carne asada, and mole highlighting diners' favorites. Roughly 20% of reviewers noted dissatisfaction, mainly with the portion sizes, pricing, or the excessive sauce overpowering flavors, as mentioned in the vegetarian menu. The ambiance and vibe receive praise for being "chill" and "relaxed," enhancing the dining experience for many, although some report tables being too close together affecting privacy. Service receives mixed feedback: approximately 85% find it professional and attentive, but a smaller percentage mentions issues like unfriendly staff or miscommunication, particularly regarding dietary restrictions. Around 10% express concerns over a mandatory 20% service charge, which some customers find excessive and not clearly communicated in advance.