This seems interesting, but the more I think about it the less I know what it would do.
What does this mean exactly? Redirect them to a specific topic that only they can see? Give them a special theme? Unlock a category only for them?
Can’t you ask them to comment on those models without even knowing what device they have?
What about people with multiple devices? Will they see different stuff depending on what browser they are using?
Maybe just have a user custom field asking them what devices they have?