Holy smokes! Just found out there is a flash kit in the making called the DSLink.
It is the same size as a normal DS game, and takes MicroSD / Transflash cards.
Card inside DS Lite:
Loader menu:
The developer said that the Castlevania intro had no slowdown at all using a KingMAX card, so I am expecting no slowdowns at all
Company site article: ( In Chinese )
http://www.yyjoy.com/yy/?p=1138
I might sell my EZ4Lite if reviews are great! ( Which I expect and most people are anticipating for. )