Nope.
Gold weapons can wait, you already have weapons, whats the point? You're going to just get a shiny new weapon even though you got plenty of other weapons.
A permanent axe means you don't have to buy ZP for ZP melee weapons, or do countless hours of surv.eys.
But sadly, there comes the "What mode you play" dispute.
If you play Ghost Mode a lot especially as ghost, axe is a viable and the smartest choice in this scenario.
If you play GR in Ghost Mode, or play any other mode that requires guns, then you best to go with the gold weapons.
AK - Gold, is easier, to be honest, more ammo, more accuracy, less recoil, more power, lighter weight, faster reload, what else do you want?
M4 - Gold has more power, accuracy, less recoil, faster reload, etc.
You have a viable option now. Make your choice. Don't take the Axe because I say so, take it if you fit what I just said.