I don't know exactly what's under the Vita front though I think there is some dev kit shenannigans going on under there (such as the bit that would make HDMI out possible even though Sony opted not to do that).
I can certainly see your issue with the right analogue stick if you have larger digits. I personally don't have a problem but my thumbs aren't particularly big.
I used to have an Ambassador 3DS, but sold it for an OOT LE Black and Gold system instead. The Ambassador games were indeed a great addition to the 3DS lineup. I still have my GB Micro for GBA games though. You know what, I take it back, GB Micro is the most perfect portable console ever!
I want more 3D Classics though, I can't wait to try SEGA's 16 bit catalogue with the 3D effect as Excitebike etc worked great with it!
RIP Dad 25/11/51 - 13/12/13. You will be missed but never forgotten.
