I have always felt secure. There have been the very occasional leaks over the years, but who knows how many of them happened for their own reasons? I figure no system will ever completely do away with leaks, but life happens, so I figure that is normal. Time and getting to know your own system lessen leaks over the years, as I learned. At least for me, itching around the stoma means the wafer seal is starting to wear away. More often than not, that gives me time to change the appliance before an actual leak happens. If I feel the warmth of product on my skin but nothing on clothing or anything, I know a leak is happening but hasn't made it to the end of the wafer yet. This has often given me time to change it before any real issues. If the worst happens, it isn't fun at all, but I learned long ago it wouldn't kill me! I deal with it and live another day.
Time has also taught me that the people around me will mostly take their cues from me. If I have to deal with it and were to act upset or panicked, they are also a lot more likely to do the same. If I act like it is all under control, they tend to remain relaxed as well.
But the Velcro on the appliance has never come open. Maybe that is the quality of the product, who knows? If I have been using a pouch for a little bit, moisture might get in the folds on the end. If that happens, I just get out a new pouch. I always get a new pouch every time I change the appliance, of course. I am glad you haven't had many bad experiences.