I have had one Vortech on a 90 for almost 2 years without a single issue as well. The newest generation apparently had some issues with some of them. I waited until a couple months ago and then bought my second Vortech. No issues with that one either. Bought the second as I am eventually going with a tank upgrade.
In pulse mode on high they can be heard to make a whirring sound but I wouldnt call it loud. My tank is an in wall and I couldnt hear it anyway but if your tank is silent and freestanding you may notice it. I can hear mine up close on other modes if I run on high but seems the pulse is the most evident but again, not what I would call loud but some have been sensitive enough to it for it to bother them.
They will make waves too, I tried it. Pretty cool but not what I bought them for. Not as good as a wave box from what I hear but the versatility is there if you want it.
I love mine, no problems at all.