We purchased our 3055 last Octomber,2005, being a carpenter/cabinet maker for 45 years, one main thing that sold me on Heartland trailer was the supieror cabinet doors and drawers with full extension slides for the value. I have had to redo the mounting of drawer tracks, but unlike the rest of the trailer, I have been very happy with the cabinets and have buillt extra drawers and picked up matching drawer fronts at the cabinet shop in Middleberry. The cabinet shop is very professional and will bend overbackwards to help you.
You do not say if only a couple of fronts are warping or if most of them are warping. If most of them are warping, I would felt what it is caused by environmental conditions. Is the trailer stored and shut-up tight? If so a sealed trailer in side is not good, we always crack open roof vents and a couple of windows. The cabinet company' phone number is in the back of the owner's manual.