Subscribe exchange is legit?

So far from all the Sub Exchange webistes - Addmefast, Youlikehits, Likenation, etc. - all the subs and views drop eventually (It seems like its faster these days - within a couple of hours half will drop) - I've been using them mostly for likes cause that's pretty much the only thing that sticks.

I honestly have no solution for gaining subs - obviously there's organic growth - but I mean by other means.

I bought subs before from several websites - mostly bots and they drop off too.

If anyone has a good method and would like to privately share it through a pm - it would be most appreciated!

What is your experience with the likes you've obtained this way? Any increase in activity?