bought a 3ds and as long as you know what your in for, graphic wise and experience you really enjoy it. in no way am i saying they lack anything, but portable gaming for me at least, is great and hits its peak for me when im on the train to school. crack it open and its juuuuuust enough mario and maybe some monster hunting that i enjoy it and put it back down until i come home. its a portable system and thats what i use it for and it does great in every respect for that. I dont however find it enjoyable to sit on a couch and try and look at a small ass screen and play a game so crammed when i have a nice computer setup to play something more comfortable. Everything has a place and where it works the best is where i find the portable consoles are meant to.
just my opinion though. i know many people who love handhelds and portable gaming all day everyday and will use it in the house and everywhere they can