Question about mediums

I currently have a DWC setup. What I started my seedlings off in were the peat pellets, now here's the question. I just ordered some rockwool cubes for some other seeds I have germinated and I have the current plants in the DWC with the peat pellets. Is it okay to transplant the current plants into rockwool because I dont like the pellets. They get into the res and Im starting to think that it's stunting my babies growth. They've only been going now for a week and a day but I still think they should be bigger. Just check my pro for my grow log I have going on here to see them. They're a lil bigger now in the pictures but nothing to what I've seen happen when people use the rockwool.

So...I want to transplant and see how they will do. None of em hae even shown any tap roots through the bottom of the pellets yet.