Using GSA For Pillowing/Diversity

So I'm considering using GSA for building my diversity links in the future. I used to build all my links manually but that takes a ton of time.
Say 95% diversity links with GSA and a few web 2.0s as tier 1s then GSA for tier 2 and 3 on those.
Do you guys think the rankings will last in local SERPs? I used GSA back in 2012 to rank some sites and I still have #1 rankings from then for some local keywords.
Let me know what you guys think.

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Yes, this can work. I usually find it best to focus on building contextual links with GSA SER for more stable and safer long term rankings. Depending on how competitive the terms you are targeting, building links with GSA SER may be a continuous process once you start ranking, as link loss over time creates a constant need to replace those links in order to keep your rankings.

No one can predict how long your site will rank for any given keyword, but as long as spam is involved, don't hope to rank for a long period of time. If your site lasts long at the top, your luck. If it doesn't, your luck.

It depends on gazillion factors but if you NEED that the rankings last, don't do it. At least don't point those links to your site directly.

You should rather build some hand-created parasites (bonus points if they're local sites) as T1 and do everything that you suggested to them. Then it should generally work much better with the added bonus of keeping your main site safer.