Oh, I'm jumping in a little late...
Singapore had always used ISI before, since there wasn't much else, not being a member of ISU. Our association has worked very hard over the years to comply with ISU rules and become a member. It is a milestone to be finally accepted as a full member, and we are still working hard to build up figure skating in a country where it is summer all-year-round (just think how many LTS skaters at your rink drop off over the summer months, and you'd be surprised we even have skaters at all in Singapore).
There has been a lot of resistance to the change from the ISI system to what our association is trying to establish. Coaches, skaters and administrators each have their own concerns and issues, but I think these will all be worked out over time.