To answer your question...definatelly not option 3. As for the correct option, there is no silver bullet. It really depends on the behavior of the user.
Flagging always helps since moderators have access to additional tools that can help see if this is spammy or not.
As for this specific case.... Thanks for the heads up.
This looked to me also like a ...
I am the one who flagged most of these spams and moderators took right action against those threads/answers. I think moderator even deleted those user accounts and it is highly appreciable.
However, it seems that LitExtension providers continues their spamming in daily basis. So I have the same opinion that of @7ochem. We should contact these extension ...
First take a look at the user profile. If you see that all of the answers (or almost all of them) are self promoting, flag one of their answers for moderator's attention and fill in a message saying "This user only self promotes". You can even put the link to the user profile.
Most probably their accounts will be suspended temporarily or deleted.
Links to personal blogs have a high chance to 404 in the future.
So, in my opinion, every answer should be read as if the links are already 404. Does the answer still answers the question?
This means that the link should be treated only as an extension to the answer, maybe an evironment to go deeper into the issue.
If the answer, by itself, without ...
Quote from: https://magento.stackexchange.com/help/how-to-answer
Provide context for links
Links to external resources are encouraged, but please add context around the link so your fellow users will have some idea what it is and why it’s there. Always quote the most relevant part of an important link, in case the target site is unreachable or goes ...
If it's in every single answer this user is posting, it is definitely spam to my eyes. Thus, the user behavior is not respecting the idea of SE and he should be flagged.
If the user posts answers without links to his website, then I reckon it's an "on the edge" case and a moderator should review it.
Just my 2 cents
So, thanks to @tripleee comment I ended up contacting Charcoal directly via the dedicated chat room.
The transcript is here if you wanna check it out: http://chat.stackexchange.com/transcript/message/33266506#33266506
So after discussing with them, they've added alerts for Magento SE:
GitHub Issue: https://github.com/Charcoal-SE/SmokeDetector/issues/277
Charcoal has brought the SmokeDetector to the next level. See this meta post: Can a machine be taught to flag spam automatically?
You can now sign up and make your SE account available for flagging spam. SmokeDetector will raise spam flags on your name through the API. The data that they have collected over the years enables them to provide a very high ...
If the answers are still valuable without the link and just include it for further reference or as source, it's perfectly fine IMHO. If not, at least relevant parts of the source should be quoted.
(I've done that myself so who am I to judge)