- No direct experience with them or other such sellers.
- Most such keys/serials being sold are VLKs.
- Almost all such 'sale' of VLKs are in contravention of the original 'terms of contract' (for such Volume Licensing Keys), be it from Microsoft Inc. or others.
- Yes, such VLKs too might work for a good part. However, if push comes to shove, Microsoft would not treat them any differently than other pirated products.
- Since as an average retail consumer, one may not have ANY real way to cross check, such 'purchases' may give a false sense of security. In reality, the freely available keys (on the internet) and such keys purchased from eBay, others
- Even if today Microsoft does provide support for even such installations, there is no stopping them from declaring such VLKs as void, banned (due to abuse, illegal sales).
- Off late, Microsoft Inc. has moved on from generally being too strict in such things.
As explained by other dimer above, all these keys are volume license keys (meaning a guy purchased/got ms volume license & now he can generate keys for his users). It is mainly supposed to be for enterprise or within a group distribution. These are not pirated, but also not completely legal as sale of those keys is not allowed in most cases to individuals outside of that group.
Microsoft also had HUP (Home Use Program, now renamed as Workplace Discount Programme), where they used to tie up with companies & employees could buy this same volume license key for 500-700rs. I had purchased office 2016 for 700rs in this way only, but here purchase was allowed as it was specifically MS HUP. Other regular volume licensing account cannot sell. But I know several people who have bought such keys and they're just working fine. Many similar websites there...
Just open MS dev account and unlimited Ms Office for free