From my experience, ConvaTec pouch system are as good as perfect.
Two piece systems
Mouldable flange/wafers .... No cutting necessary.
Convex flange/wafers
Self adhesive pouches
Click On coupling pouches
Various capacity closed pouches
During my time usung ConvaTec appliances, I only had one or two quality control/manufacturing issues.
Where as with products from other recognised brands, they always failed, some within hours.
Once a product fails, confidence in that product is lost.
The issues I experienced with ConvaTec products were relatively minor and very quickly resolved and didn't result in serious leakage or complete failure.
I hated my life with a Stoma, especially just after the removal of my bowel and some of the products provided by the Hospital compounded my feelings, but the ConvaTec products made my life with a Stoma all the more bearable.
I felt so secure wearing the ConvaTec 2 piece appliance and my Comfizz boxer shorts that I was able to complete day to day activities without the constant fear of leakage, which I was unable to do when using ostomy products from any of the alternative brands.