Does NRT and facet search work together?

Hi,

Does NRT work well with facet search in ElasticSearch?

Does faceting in ElasticSearch rely on caching (which I believe is how faceting is implemented in Solr) for performance? If that's the case then wouldn't NRT reduce facet performance significantly because all the realtime updates are constantly invalidating the facet cache?

Any tips on making NRT and facet work well together?

Thanks.