Personally it depends on the product whether or not I'll buy a brand I dislike. For example, I'm not keen on a supermarket brand of tomato sauce here but it is the cheapest. However I'll buy it if I'm using it to make a barbecue sauce, as I can't taste it then anyway so it doesn't bother me so much. If I'm using it as is though I'll opt for a different brand so that I enjoy my food more, even if it is a little bit more expensive.
Price and quality matter more to me than the brand itself. I mean, I understand that there are such things as "trusted brands." But just because you can trust certain brands, that doesn't mean lesser known brands aren't capable of producing of cheaper and more quality items. I try to see the product itself, brand regardless, before I make any purchase decision.
I would not buy that brand because it would be cheaper. I would have developed a bias against it for some reason or the other and the mere reduction in cost would not be enough to change my view on the Item. There would have to be some improvement in that aspect of the product which had caused me to reject it in the beginning.
I'm always trying cheaper brands. Initially the taste will be different I've noticed but in time if I keep using it I get used to it. That said, if I buy a cheaper brand and I can't stand the taste then I'd forced to buy [the next time I go shopping that is] the brand that costs a little more because at times you also have treat yourself well. It might even motivate you to find other ways to save money.
I agree that you can use a lesser quality brand of something if it's going to be part of a sauce. I have no problem buying a cheap tomato soup if I'm using it as part of a sauce which I'm adding a lot of ingredients and flavour to. I do like to use certain brands of ketchup, pickles, spaghetti sauce or pasta. I just wait until they go on sale and then I stock up my pantry with them. There are some items I don't mind buying a lesser quality and save some money too. I do this with canned chick peas, canned beets, and dry goods like baking soda.
I almost always look at the price first so I do consider it but I wouldn't choose it if it means I'm giving up a significant amount of satisfaction or comfort for it. For example, I could go for cheaper or store brand pasta because I know I wouldn't be able to tell the difference, but when it comes to sauces I will choose popular brands if they taste the best and the small increase in price is worth the cost to me. I feel the same way for sneakers too since I will be wearing them for long periods of time and I feel the comfort is worth the extra cost.
Most often I am generally pleased enough with generic and store brands of products, and will gladly buy them in place of brand name items to save money. But there are some products I will not buy simply because they are cheaper. For example, I was making stuffed peppers one day, and tried to use a cheaper brand of tomato sauce I had gotten from Dollar Tree. Admittedly I should have tasted the sauce first before using it on them - but the sauce ended up ruining the whole pan of stuffed peppers and I ultimately had to toss them. Another item I won't buy a cheaper brand of is mayonnaise - in my experience, many of the cheaper brands don't taste as well and are greasy.
