I just ticketed a DONE4 for my parents leaving from ICN in October, with the AA GSA in Seoul.

I was really quite an effiencent process. The only bug is that tickets need to paid for at the office in person, not over the phone.

The GSA is also the BA GSA, and the front desk has one BA agent, and 2 AA agents in airline uniform sitting next to each other. Trying to get though to the the office on the local phone number for AA is a pain- over 2 hours with numberous attmepts, but in person they were very quick and friendly.

The pricing was very good as well. The base DONE4 fare was 5690700KRW, which is about US$5430. The routing was not mileage optimised, though it does have 16 sectors. The taxes were just on $490. I will happily use this GSA in future (as long as Korea has such good pricing).