Well on build quality and quality of materials you would be thinking along the lines of peugeot,citroen or renault.
My first choice wouldnt be to go for a car thats known for great reliability. I choose the drive first. Buy a car for the reasons that will make you happy with the purchase because of the way it will meet your needs. Theres no point in buying a mondeo if people consider it as being great value and reliable if you drive around in it feeling suicidal with how boring it is to you.
You might be looking for that,though.Nothing special.Just a good functional car to get you around.
I`m the opposite.I drive a french piece of crap thats rusty,it leaks on wet and windy days,its always got a wee rattle here and there.Its not great on fuel like my diesel but its the drive that makes me keep a hold of it.
So to answer the question.. the brands of cars that are considered boring and are super reliable.