So I just inherited a bunch of CD's and some are made overseas...

CD's like LP's can vary in sound quality from cut to cut ... and also from CD to CD.  

I’d keep the ones made in Japan. They are typically a higher quality.

As a general rule as with LPs I’ve often found that the original CD from the country of origin of the artist sounds best. This was definitely true of the Kate Rusby CDs I collected. Here I’m referring to first issues not teamsters of old material

I have multiple CD issues of the same artist from the US, West Germany, EU, and Japan. These are original flat pressings, not remasters.
There may be differences in dynamics, high and low-end extension, soundstage, 3D imaging, and noise-floor resulting in more separation between instruments. Early issues may sound different than later issues and there’s no guarantee that a first pressing has better SQ than a later release.

Typically I like the SQ of German releases (later issues are labelled as EU). And I’ve found that Japanese pressings are consistently of very high quality.
    Of course, you must have a high quality CD setup to reveal these differences.