I love both systems, the 3DS has more games that correlate to my tastes(rpg's, puzzle, life simulation ect).
Are you aware of all the currently released and upcoming releases for it?
Edit: Actually, if the 3DS does have Metroid Fusion, Minish Cap and other GBA games is you're an ambassador.
I'm kind of in the same boat. I like both systems, but Vita aooeals to my tastes more. 3DS has a strong lineup this year, but few of the games actually interest me based on my gaming preferences, which are action games, and RPG's.
I depends on your personal tastes. If the 3DS does not have the current, retro, or upcoming games for you, then by all means sell it. Sure the chorus is saying that the Vita is a flop, theres no games, etc., but there are plenty of people who are satisfied by its particular offerings. I am one of those people.
In my humble, opinion, Nintendo cannot make a worthwhile hardware for their life anymore, and the games have suffered since the N64 days because of that. I'm a fan of niche Japanese style games and RPGs are an important part of that. The Vita's selection of PSP and PS1 classics severely trumps any RPG offerings for the 3DS, either now or future in my view.
The 3DS is a console that can satisfy a specific craving for Nintendo first-party style games, and 'dumbed down' games of other genres, imo.
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