So is that what we're defining "good" as? Something that would cause you to make a new team?
Absolutely not.
I mean, look at it this way. The case you have is that you are using them to change the color of an enemy so you can resist them. Most workable teams nowadays just have means to reduce all types of damage, or straight-up have HP/RCV mults, which also work for all types of damage. ReGreeks are probably the only viable team as of now that even use the color resist gimmick now, and only three of them work with the puppeteers.
This leaves using them as an extended damage enhance. How many other teams that are NOT ReGreeks even need to stack this much damage to kill something? Is this something that cannot be solved by other means like using gravities, shields, or other enhances? I think most mults today are high enough to deal with most enemies without the need for this. Which means the sub slot can be used for a card with a more readily usable active, better stats, and better awakenings. Just to put into perspective how comparatively bad their stats are, Pure has a WST of ~685, and ORIGINAL R/G Leilan has a WST of ~745. That is fucking terrible, weaker than a card from like 2014. With cards now pushing 900~1000 WST without inherits in 2017, that is a lot of potential bulk you could be missing out on, as well as another active that could be... whatever you want, really.
This doesn't undermine the fact that you
can use them in lieu of all these things, since the brunt of these things rely on what the REM gives you, but with how generous the game at this point, I feel like they're an afterthought to most people, and probably why Chaore is only considering the buy if too much MP accumulates. Speaking from experience, even I don't use Pure that much, and honestly mostly because she fills colors in a color-required leader and has two time extensions for casual play. All probably depends on how much you value your MP, and what you're expecting them to churn out in the future, especially since they're up to 750K purchases now.