Well, as the above exchange should tell you, it depends on:

Are you willing to spend money on this game?

If so, gold units will end up being expendable in the long run. If not, it's recommended to hang on to them.

Assuming you are NOT going whale (big spender), it also depends on what gold unit. Bernice and Iris are mainstay gold units that are worth CR due to the fact they are highly useful and used often. Anemone is a great gold if you did not score Sabinne (the fact you're asking makes me pretty sure you don't have Horace) let alone Sybilla, since ranged magic attack has its uses. Julian is a more offensive alternative to Katie (higher attack, lower defense, same skill but easier to CR) and if you do CR/SU him he becomes preferable for the primary role of soldiers if you don't have Jerome (plat soldier). Kerry is a solid UP ramp if you don't have Dahlia, Thetis or Clissa. If you missed Belinda and haven't scored Adele or Despara, Yuyu is fantastic (even if you have all 3 of those, she has her uses). Zola is great for AoE physical damage, and Mehlis is a good mage (doesn't match up to the plat and black ones besides cost, obviously).

Ultimately, the biggest question is: Will I use this unit a lot? Most gold units are great for non-spenders but even spenders will get mileage out of Iris and Bernice, but some are just plain used more often than others, and some you might have alternatives for already. Did you pull Thetis? Kerry just got a lot more expendable. Got Jerome? Julian can hit the hay. Sasha/Garania? Not much use for the gold mages.

Also, the most common classes for AW fodder are soldiers (Gold: Julian, not counting Katie because she's currently unique), witches (Gold: Yuyu, Cloris is unique), Valkyries (Gold: Kerry), Healers (Gold: Iris, Fedora), Heavy Armor (Gold: Bernice, Garret) and Mage (Gold: Barbastroff, Mehlis, Cyrus). Out of those, the more "expendable" gold units are Fedora (generally outclassed by Iris as a healer), Garret (totally outclassed by Bernice for the job of a HA) and both male gold mages (Mehlis outperforms both under most circumstances).


Regardless of what you do, make sure you have units that can fill the role of the gold you're discharging or using as AW fodder. Last thing you need is to use your only Iris as AW fodder and be stuck with silver healers, for example.