The answer to which handheld/microconsole will sell more is obvious as heck.
However, I will say that the Vita Slim/Vita TV are better for gaming. PS+ and cross-buy/play are absolutely great for the Vita. The Vita is also not region locked, thus any game can be played. In fact, I'm playing the Chinese version of P4G right now. 
The Vita TV should help boost the userbase even if only temporary. The platform does have a good library, but the average consumer doesn't know that because of Sony's inept advertising of its games. But games like SAO: Hollow Fragment, DanganRonpa 2, Disgaea 4: A Promise Revisited, Digimon Cyber Sleuth (if it ever gets localized), and more are worth playing.







