If the body line is alittle dented would you suggest replacing everything under the top lip? Or is it not to hard to fix the bodyline?
Full disclosure, I'm not a body guy nor have I stayed at a holiday Inn anything.
I'd be worried about warpage plain and simple. The body line can certainly be re-established, it's time, patience, tape and probably some filler. Most of the bodyline will be established when block sanding the primer. Tape the line on one side, then block sand "to' the line. Switch the tape to the other side, then block sand "to" the line from the other side. Probably easier said that done.
Again, MY worry would be the potential for the panel to warp etc. At least on a challenger, there is a "hard" body line which would make it LOADS easier to replace the lower skin only.
To answer your actual question though, I'd opt to fix the panel rather than replace. Lots of people think a dent is a reason to replace because of a false aversion to filler. You're going to have filler, period. how much is up to the skill of the person fixing the dent or replacing the panel. Filler up to a nickel thick is no big deal.
as others have said, pics would help.
-=C