I am pretty specific about the products I use anymore. I like the SW products because I know how they work.
I have customers all the time asking about different things they see on TV or read about online. I will research it and give them my thoughts. Usually I can get them to use the product I prefer, but not always.
If it is something like interior paint, I don't really care so much and just keep my mouth shut and deal with the extra drips or coats.
If it is something like a deck stain, or exterior paint that needs to perform, I will be much more insistent.
Most name brand paints are decent enough, but there are times where you need to know how a product will perform in order to deal with extenuating circumstances or problem surfaces, etc.