What Alex said. Bedded the pads in properly Jardo? I have had the discs glowing red on Stan's Clio with DS2500s fitted and they worked spot on, also work perfectly well from cold and everywhere in between.
Warped discs is a myth, it's pad pickup, which makes itself worse by grabbing harder at (the slightly wider) same point each time the disc goes round. Sand the discs down or get them skimmed, then bed pads back in with hard braking.