Rose gold has this reputation for being the soft option, the shade you pick when you can't decide between gold and silver and want to look like you made a choice anyway. I used to think that was a bit of a cop out, but I've come round to it. It sits closer to skin tone than yellow gold does, so it tends to look like it belongs there rather than sitting on top of you.
It works hardest when it's not trying to be the only thing you're wearing. A fine chain under a plain jumper, a pendant against a white shirt, even stacked with a thin gold or silver piece so it doesn't look like you're making a statement about metals. Where it struggles is against anything with a strong warm tone already, deep orange, certain reds, it can start to look a bit matchy and accidental rather than deliberate. Against navy, grey, black, white, it just works without any negotiation needed.
The shade itself varies more than people admit when they're selling it to you. Some rose gold is a proper dusty pink, which is lovely and wears well for years. Some is closer to copper, which looks warm in the shop and slightly brassy under office lighting by the second week. The paler, more muted pink tones tend to be the ones that still look good after a hundred wears, rather than the ones that looked best on the stand.
The difference between a good one and a bad one is almost always in what's under the colour. Solid rose gold, or a decent gold vermeil over sterling silver, keeps its colour because the pink runs through the metal or sits as a proper plated layer, not a flash coating. The cheap end is usually a thin plate over base metal, and that wears through at the clasp and anywhere it rubs against a collar, going a dull yellowish grey underneath within months. The clasp itself tells you a lot. A lobster clasp that's stiff and fiddly on day one will be worse once it's been opened and closed a few hundred times, and a chain that kinks easily at the link is a chain that'll eventually snap at that same kink.
Before you buy, run the chain between your fingers for snags, check the clasp opens properly rather than needing two hands and a swear word, and look at the join where the pendant meets the chain, because that's usually where things fail first. What it won't do is stay looking freshly plated forever if it's not solid underneath. Even the good ones will dull slightly with years of perfume and skin contact, that's just what happens to anything you actually wear.