Restoring a Windows 7 OEM install is not always what is wanted or the best idea.
Using the backup recovery partition or disks made with the manufacturers supplied utility program will also reinstall all the bloatware/trial software/potential spyware that was included originally.
It can take longer to remove all the junk afterward than it does to do the actual install. And you can never be sure it's all completely gone. It is guaranteed that dregs will be left in the registry. A clean install is often (usually) the better plan of action.
Offline activation of a clean install is not that difficult as long as the necessary files are copied beforehand and there have not been hardware changes. Be sure to download in advance any drivers you might need (chipset, network, video, sound, etc.).
I agree that a major downside is the useless bloatcrapnagware they slot in, that only serve to bog down performance and give the OEM vendor a bad rep and lost future sales,
with a good chance the burnt buyers go 'Mac' and try their computing luck there
FWIW I keep 2 separate backup images of the entire OEM PC
one in it's original shipped state,
and another image after all the bloats have been removed, Registry leftovers nuked, security scan, and updates and service packs applied,
which sits on any external USB drive nicely, ready for a rainy day...
There's also a third image with apps etc and or another when the PC is running really well = backup
I'm not a fan of cloak n dagger activation games BS, so I take the easiest surefire legal -CHEAPEST- way out, new or used.
Admittedly most OEM PCs may not be spec'D gamer class machines, but throw in some extra ram, optional decent graphics card, a 7200 rpm or SSD drive (or two) and they do the business for most tasks good enough
Why think about Windows or Linux when you can dabble in both or as needs dictate
Linux costs nothing and I reckon if I got really serious about it and over the 'Windows or Mac' duopoly, I could have a distro or two running like beasts with all the apps I and the locals around me need.
If I need 'support' or handball tips to newbs, apps, workarounds and the latest browser and whatever, Linux user websites and forums are a Bookmark click away...
MS and Apple should tread carefully with their expanding money pits, lest the connedsumers and corporats get fed up with the BS and
'give something else a try and see how it goes...' Playing with Linux means you can pull the plug on Windows and Macs any time without too much drama, and have a fun weekend or two sorting it all out and exercising the brain,
on most bog standard PCs, even older ones dating back 10 or more years
For gamers and serious AV users my blab above may not relate to your needs, in which case better off having a separate purpose rig anyway with a wired internet connection, which is usually the norm I think