Although there isn't stiff competition for Chinese restaurants in downtown Pittsburgh, I'll still give Mandarin Gourmet credit for being the best of the worst. Overall, I would say the quality of their food is very good for the price and portions they're serving. One order usually has me eating General Tso's for the next few meals. The lunch specials have even better deals, so if you're a penny pincher like me, jump on those discounts. My usual is the General Tso's Tofu which is amazinggg! Crispy tofu wins my heart every time. Their Mei Fun is also another great option I highly recommend. However, like most Chinese places, steer clear of the sushi. Just don't do it. It's more disappointing than their stale fortune cookies.
Don't be surprised if you experience rude customer service for dine-in. I've had a few run-ins with grumpy or nonexistent waiters, so I do take-out whenever possible. Less wait time for food and limited social interaction - best combination.