Moving from Heightmap to Quantized Mesh Terrain

We currently have an AltitudeManager in our client side code that caches terrain data we have already seen by listening to the "newTerrainData" dojo topic that terrain tiles are published to via the HeightMapTerrainData class so that that (lon,lat) altitude lookups are fast. However, we are trying to switch to Quantized Mesh, which does not give us this level of insight. Has anyone else done this kind of caching so that (lon,lat) altitude lookups are fast using Quantized Mesh? I really don't want to do a REST call to the terrain server every time I need a lookup.