I love Faryab. I live in Bethesda and will often bring my out-of-town guests here. If you want to go to a high-end chain restaurant and rub elbows with folks dressed-to-impress, go to Bethesda Row. However, if you're interested in a different experience, go to Faryab -- a tucked-away family-run gem that is authentic, comfortable, and makes you feel at home. There are white tablecloths and napkins, but no pretentions at this place. And the food is wonderful.
My favorite is the Quabili Pallow -- the lamb dish with carrots and raisins. Simply amazing. The Kofta, Aushak, Mantu, and Chalow kadu are also terrific. (Who knew pumpkin could be so good!) I have never had a bad meal at this restaurant, and my guests have always loved the food and the ambiance. (The noise level is very low so you can actually talk with your guests!)
While Faryab tends to attract adults, I have taken my kids (now teenagers) to this restaurant since they were five. Whether it be the special treatment that the waitstaff provided or the realization that they were in a "different" restaurant (i.e. white tablecloths), they love this place as well. When they were little, my kids would order the basic kabobs (not spicy). Now they are comfortable ordering the more "daring" dishes.
Incidentally, the one negative review in TripAdvisor has been "cut and paste" in any number of DC reviews (for example, Washington, DC menu pages). This sounds like someone who is on a little vendetta as opposed to writing a true review.