Replying based on Experience. I have a 80k IG account and 3 DM Engagement groups about Pins and Patches.
Bad Parts - Reason why I left all of them.
* The effort required to maintain this groups is huge.
* You cannot bot it cause people there are bigger than you or on your level of followers,
* If they see you botting they'll go out of the groups sooner or later, so no use. No General Comments and such, if you want quality provide quality.
Here's the math
1 Group = 14 other people +1 you max (only 15 per group)
14 people x 3 groups = 42 people.
-- 42 people all are active (that's what you wanted right active posters?)
42 x 3-6 posts per day.
We are talking 126 upto 250 Real live likes and comments on a daily basis that you will do.
And not to mention this 2 hard things
1. you are required to do it because they are doing the same to your posts.
2. You are not in the same timezone. its hard to form a group of high follower DM group all with the same TImezone etc. SO you like check every 3-4 hours and spend 1 hour per wave finishing up the others who posted.
Good thing about it.
I stared about the bad thing because the results are really that good. It is working. Comments are going up. Likes are 30% more, higher chances of hitting the Explorer page. It is a good method specially if you form or had been invited in a Niche related DM Engagement Group. It makes your posts explode.
So is it worth it? Yes Absolutely. But why did i quit using the method? I need more time for other campaigns so this time consuming tasks, i will either pass into a VA only but not me.
Just my 2 cents