What’s your process in figuring out if a concealer is working well for you?

I have to wear it for at least a week (consistently or else a week’s worth of wear) and see how it pairs and blends with other foundations and mascaras (I find that some foundations/concealers can make a mascara more prone to smudging!). I’m getting to the point where I sort of accept some limited amount of settling/creasing in my lines over time but want a concealer that covers quite well, doesn’t emphasize my lines or dryness, and doesn’t stay settled in my lines initially.

— Christine

Source: FS – All – Cosmetics & Spa blogs
What’s your process in figuring out if a concealer is working well for you?