Apple has recently done a lot of work upgrading the grading tools in FCP X and it's now got the ability to have multiple LUTs applied (including creative ones). So, before buying add-ons like Finale, I'd check out the tools built in and see if you can manage to use those to do what you want. Ripple Training have a series of free videos on their youtube channel which will introduce you to the new FCPX color features, and they've a bigger set of paid tutorials for colour correction in FCPX if you want to go down that route.
I do have Color Finale Pro, but so far I've really only needed to run it on a couple of projects. It is useful if you have a Color Checker video passport as you can get auto correction using the passport swatches (I think that's a feature available in DaVinci Resolve too).