You people are talking about two very different things. Medications and consumable products are apples and oranges in the generic world.
IMO, for consumable products, it really depends. As most have mentioned there are specific products where quality matters (toilet paper and paper towels for example), and then there are others where generics really wont matter much other than packaging (last time I checked there are no "brand name" cows giving milk or "brand name" chickens laying eggs). Basically, you need to figure out where that sliding scale is for you regarding quality of life and frugalness. I mean, how far do you want to take this whole "saving money" thing?
"It's okay, its clean"
*On the Rx medication front, I can assure you that the
active ingredients are just as pure and effective as those in the name brand meds. In fact, the medications are often made at the same factory by the same people, using the same machines and ingredients. There are laws and regulations in place (within the US anyway) that make sure of this. So basically, if you're looking at the
efficacy of the medication, generics will be equal to the name brand in every way.
Of course that's just talking about the active compounds. The main difference is going to be taste/smell/size. The companies that make brand name products use a lot more funding to research and buy binders, colors, flavors, etc which are just
better. Ever wonder why your generic pill is like 3x as big as the brand name? Its because they use a cheaper binding agent and there's a lot more of it. Same reason why some generics taste or smell like crap compared to the brand names. This can also lead to other issues if your body doesn't like these cheaper "non active compounds" in the generic. People with these sensitivities can have issues like getting an upset stomach, etc...
The best suggestion here is to ask your pharmacist what he/she thinks about the generics vs brand name. They will be able to get right to the point and lists the major differences (taste, odor, etc) as long as you make sure to let them know you're aware the active compounds are the same. In fact, I suggest asking a pharmacist over a doctor since the former is the one who deals directly with the medications on a daily basis. It's literally their job to know this stuff.
In any case, given the cost difference its always best to at least TRY the generic (unless your MD or pharmacist tells you otherwise) first. You can always switch to the more expensive stuff later if need be.
*Citation: This information comes directly from my lovely wife, who finished her graduate degree at the USC School of Pharmacy.
edit: I guess meds and consumables aren't so different after all. It all just depends on each individual, lol.