for me it depends, i personally hate MULTIPLAYER games that can give players an edge due to weapon customs:

GOOD:
-16 players all have lame ass SMG
-1 player emerges as the winner, so you KNOW its ALL about his skill

BAD
-15 players have lame ass SMG 1 player has lame ass SMG..... with scope
-he emerges victorious.. ummm, i wonder why

that could easily be said for any other addition, in a multiplayer settings, all players should have an equal chance and not gain an upper hand due to weapon mods...

in a single player setting, sure its no problem, it hugely depends on the style of game you want also...

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