Hi gaogia... i am answering you just from a consumer point of view , if you are in the unfortunate position that the refurbished drives fail your consumer rights are stronger than if the item was brand new.
New anything can fail because they have never been used but refurbished computers or components must work when resold. The key phrase to quote for a refund if they go faulty is " not fit for purpose "
First, thing, calling me gaogia is actually really insulting I hope you didn't mean it that way not knowing how my username/real name means etc. more than likely a type error?
Anyway back on topic, yeah, I am looking to try and get my macbook pro running one again, its an older model, 2009 and can't buy a new logic board, I can only find refurbished ones, searching for them I found this website, I would go without than buy refurbished, I have only once brought something second hand (well 2 things, my car) which was my AV receiver, which was what I really wanted then they discontinued it when I saved all the money for it, Couldn't find one anywhere, eventually I found one, where they man in the city I live brought the same one I wanted (about 3 months before) but he got a better one for his birthday and was selling the one I wanted really cheaply. I ended up buying with the money I had saved, an Airport Extreme, and an Airport Express with more money left over.
I am autistic, and disabled where my spinal cord is compressed and my ankle is shattered (both can't be fixed) I am in a lot of pain, and take a lot of morphine daily, and it means I can't really sit at a desk and play games, which I am only playing games I know at the moment but there are so many I want to play, which is why I built my PC, I know its not the best spec, but it should be good enough for me.
I think I have enough hard drives at the moment, but where is the best place hard drives to get when or If I need more? The cloud was mentioned and how can I put my data, pics etc on the cloud as a third backup?
I am sorry for the long post, but how do I know from a good hardware component to a bad one, I am thinking Macbook pro fixes here. Would I be wiser to find someone who can fix my board or buy a "working" refurbished?