Is this windows 7 the same as the other windiow 7in terms of wquality ?
Yes. Once installed, it is all the same.
And to reinforce the earlier reply: (from the Amazon link, emphasis mine)
"This OEM Windows product IS NOT an upgrade product. This Windows product does not come with Microsoft support and requires a clean install
, which is complicated and will not save anything currently on the computer"
"OEM is not intended for consumers to directly upgrade from older Windows Operating Systems. It will require a clean installation
and so all prior data must be backed up."