Rapid Rooter Transplant Question: Seedling to...?

We germinated 3 NYPD and 3 AK48s from Nirvana in rapid rooters, as we were hesitant to use rockwool. It's been about 5 days and they have all already sprouted and the tap root as well as other root shoots are coming through the bottom of the rapid rooters. When should they be transplanted and what should we transplant them into? We're using Cap's Ebb & Grow bucket system with hydroton as the medium. Should we simply transplant the rapid rooter into the hydroton in the 2 gallon bucket it will grow up in, or do we need to transplant into something smaller first?

Sorry if this is a total newbie question, we're newbies... And most of what I've seen only has to do with transplanting clones from rapid rooters. Any and all help would be most appreciated.

put it right into the 2 gallon pot, just put it into your medium and it's ready. when the roots are showing out the bottom that quick, you got a girl that is a fast grower and needs room to spread out.