How many layers of FG did you use? I personally did one coat, then fiber and then two mor coats and it is holding up to dropping, bondo and sanding.
Here what I have so far, needs lots of work.
[ATTACH=full]82087[/ATTACH]
[ATTACH=full]82088[/ATTACH]
[ATTACH=full]82089[/ATTACH]
[ATTACH=full]82090[/ATTACH]
[ATTACH=full]82091[/ATTACH]