Like many we started with clit vibes. It wasn't until we tried a rabbit (dual stimulation) vibe that the thought occurred to either of us. When she would orgasm with the Decadent Indulgence link
but would not let me use the rotation feature - I asked why not just a clit vibe - that's when I learned that she liked 'something to squeeze' while having an orgasm.
Based on that I started buying dildos - now things are all turned around. She has one or two favorite clit vibes to use while I fuck her with one of the 20 or so dildos that we have accumulated. And BTW now she likes the rotating feature of the DI as well!