I buy a lot of goodmark from rockauto and it all has been good fitting parts, metal is plenty thick too. I can't speak for those exact fenders though. Everyone here seems to love amd... and of course a lot of people sell it on here too. Worth 400 more for a pair? I doubt it, but to each their own.

68 Road Runner, 69 Belvedere, 71 Challenger Vert
340 barracuda, 01 Ram CTD, 95 Ram, 04 Ram, 85 Daytona turbo Z
66 GTO, 06 Magnum RT AWD. 07 Ram CTD, 07 Ram