Honestly, X/Y are brilliant. It's a massive step forward in the Pokemon series. I myself have Y and have put over 50 hours in it so far and still going on! The controls are a bit awkward at first but once you've played for a couple hours you'll be used to them. Using the 3D during battles can result in a frame rate drop which is a slight shame but considering it's never been done with Pokemon and it's all new, it's not going to be perfect first time is it?
With additions such as mega evolutions in it as well, it just adds to the enjoyment even though the evolutions are limited. The pokedex is also split into 3 (4 including the national) with 150 pokemon in each section. It's good as it is not 450 completely new pokemon but there are a lot of older pokemon that fans of the series will also recognise so we aren't met with lots of ugly new pokemon, even though there are some in the game (But it's the same with every other pokemon game).
The character customisation is also a very nice features with the ability to buy new clothes and bags which is a small feature but is just a nice aesthetic and adds to the character and feel of the game.
Difficulty is not very high though, it's quite easy in comparison to games like Generation IV Diamond and Pearl (If you've played them). But I guess it will depend on how much you A) Train your pokemon and B) The types you are using.
I could write a lot more, but I don't want to have a wall :p. In conclusion, it's a brilliant game and is well worth buying a 3DS for. Of course the 3DS has other games which are amazing but X/Y are both brilliant. Whether you're new to the series or a veteran, you'll enjoy it.
Final score: 9.2/10