Jon Carter
Member
IIRC, for the very few Vita/3DS multiplat titles that exist, the vita version has always outsold the 3ds version.
That's not actually true. I can remember at least two 3DS/Vita multiplats that sold better on 3DS in Japan.
Also, it's highly likely that many Vita owners also own a 3DS. If the Vita version is technically superior and prioritized in the marketing, it's expected for owners of both to go for that one if we're talking about a niche game. The size of the install base is only going to matter for games that are aiming for a wider and/or larger audience.