I've exhausted all the JRPGS on the Sony consoles for the time being, need to explore the more on the other side.

JRPGS I already own on the DS: Suikoden Tierkreis & radiant historia.

JRPGS I own on the 3DS : Pokemon Y

Only picked up 3DS last week so havent played it much cause of exams so don't really know whats good and whats not.

There's so many good ones. I'm too lazy to list them all. :/

But, these are my favorites (that you don't already have):

DS
Chrono Trigger (it has extra content)
Dragon Quest V: Hand of the Heavenly Bride
The World Ends With You
Any and all Atlus RPGs.
Mario & Luigi series

3DS
Fire Emblem: Awakening
Any and all Atlus RPGs.
Kingdom Hearts 3D
Mario & Luigi: Dream Team

Tell me about thi extra content for Chrono Trigger :D

Fire Emblem was one I was looking at today, but it cost $90 NZ which is the same price I pay for brand new games. So im on the look out for a 2nd hand copy.

The same additions to the PS1 port, plus two new areas, a monster battling arena, and an extra ending. There's also some new features, like an autofilling map on the bottom screen, the ability to set running as the default movement, an optional battle menu layout that utilizes the touchscreen.

Random list I found on Giantbomb =) have no idea if there good personally as Ive never playerd them. 

Dragon Quest IX 
Final Fantasy IV 
Final Fantasy Tactics A2 
Fire Emblem Shadow Dragon 
Front Mission 
Infinite Space 
Radiant Historia 
SMT Strange Journey  
The World Ends With You 
Xenosaga 1&2 (Japanese) 
ASH (Japanese) 
Suikoden Tierkreis (Japanese) 

Golden Sun

Etrian Odyssey

Luminous Arc

Final Fantasy III (the remake of the real one).

Already got that on vita, only beat the first boss though.

The 3ds is my first portable, so I won´t speculate about Ds rpg´s

Some good games on 3ds are: Shin Megami Tensei IV, Etrian Odyssey IV, Fire Emblem (more strategy than rpg, actually), Mario & Luigi Dream Team, Paper Mario Sticker Star, Rune Factory 4, and (some people will bash me on this, but I do think it´s a good game) Heroes of Ruin

They ported it to the Vita? Sheeeeit...

Then again, I can't remember the last time I saw an ad for a native Vita game, so, guess I can't be too surprised.

To the PSP, I think.