I recommend the Bucheon Sangdong Jiin Oriental Medical Clinic.

I had gallstones, so I went to acupuncture at a friend's recommendation. The needles were placed so well that they were painless, so I highly recommend them. They also offer evening treatment until 9 p.m. on weekdays, which is great news for office workers. It's also conveniently located near Bucheon City Hall Station, so if you live nearby, it might be a good idea to visit when you get acupuncture.