One drawback is that the former skeletonized panel will interfere with the backside surface of the "new" panel, making instruments not fit with the flush mounting intended by the designers. Mounting screws will be (possibly) too short, and some corners of the instruments may not sit flat against the panel. These deficiencies may be acceptable to some, but not to me. I'd rather go the extra mile and do it right with a new panel, like I have done four times in the past. I'm getting better at it, too!