DTF is a Taiwan-based chain specialising in Hu (Shanghainese) cuisine. Fried rice is not their forte. Wok hei is a foreign concept to other schools of Chinese cuisine outside Guangzhou.
The HK Cantonese restaurants do better fried rice with more wok hei anytime. Money no object, the best fried rice I've tasted is at Jiang Nan Chun (Four Seasons).