Good question! I only have like 2 "traditional" vibes, and one wand-type vibe. The Fairy Wand gets used pretty often for massage-type "foreplay," the two insertable ones are pretty much mainly for solo use.
But dildos (which comprise the bulk of my collection) are used both solo and partnered. Wonderful as my fella is, he doesn't have two cocks
so I'm very grateful to Tantus for stepping in!