PPE manifolds & up pipes, Duramax store brand or???

I just ordered WCF turbo intake horn, cold and hot tubes, y-bridge, aircleaner setup and down pipe for my ride. It's a low mileage Cali emission rig we're fixing to delete and tune with EFI.

Got everything else bought today but manifolds and up pipes.

Anyone have any input on brands listed in the title or better ones??

Duramax store has best price on theirs but like to make sure they are as good and flow equal as the others?