I'm getting a second flash cart, and I was hoping I could use it to trade my old Pokemon from Soul Silver to Black version. However, recently I've been reading stuff that hints that trading won't work between flash carts since the Relocator and PokeTransfer use DS Download Play instead of in-game trading, which doesn't work on Flash Carts. Is this true? I'll be trading between a DSi and DSL, if that is important.