I have had 3 distinct experiences with customer support.

I have received the "Yes, we know about that and we're looking into it" regarding a Cerberus/Baal glitch where I'd get stuck on a rock for the final battle and for the disconnects when they push arena rewards during wb fights.

I had a rapid resolution to my report when I was charged gems for something and it never anywhere said I'd be charged gems.

My biggest concern, however, is that I have yet to hear about a report of harassment being taken seriously. I have gotten the form letter "we can't tell you anything we did to resolve it due to privacy concerns" which is fine. But it's patently obvious they've done nothing when the culprit continues to log in and be a creep. These reports are including screenshots and updates as often as the infractions occur but I do not think harassment reports are being taken seriously at all.

Actually, there is a fourth example. I misunderstood a game mechanic and reported a bug. I received a proper reply within a few days to explain the mechanic. So I consider that a positive resolution.