Kevin:
At this time there is only a workaround of using the General - Gazetteer locator style when building the locator and publishing it as a geocode service. The Gazetteer style does not have the memory leak when used as a service with suggestions. It also has the logic to handle spelling sensitivity.
Whatever field was used to map to the Keyfield in the Single Field style, map it to the Place Name field in the Gazetteer style.
-Shana