Case quality is nowhere near GEC, but it's hard to compare as GEC is 2-3x the price. I will say I have never had a GEC with an issue. Pretty much every Case I order sight unseen has issues with liner gaps, blade play, centering, and even blade rap, not too mention not great walk and talk.
I went to buy a Case at a large knife store in TN, and couldn't because of the 3 knives they had in stock, they all had blade play and other various issues. When you DO get a properly QC'd Case, they will rival GEC in quality. I just wish Case offered more Carbon blades, but I understand why they don't. I wouldn't mind paying more for Case if there QC was kicked up a notch. They have a lot of great patterns and covers, and are available. At this point, it's not worth the hassle to buy unseen. Now I will say if you have an issue with a new knife and can't exchange it where you bought it, Case will fix it, and they will do it relatively quickly.
But, like I said, it's hard to compare the two. I buy both brands, but I'll buy GEC sight unseen, Case I need to inspect first. Overall I'm grateful for Case, and I'm happy they exist and will happily support them.
Also, Case knives are sharper out of the box.