Tube assist... what features are still working well? Issues with subs?

I put up a music video a week ago that is on par with all of the related channels I targeted. Haven't told anyone organically about channel yet, just doing some tests while I wrap up the website.

Anyway, using tube assist for a week doing subs to those who comment on other channels with very similar music, and so far, not a single sub back.

My video is set as featured video, and I think I'm doing everything else suggested. I know there are other things to do like comments (I really don't want my channel's name on spammy comments, so I'd prefer to do those manually), and sending vids, messages, etc. I just wanted to start with one activity so I could track. Video is good quality, music is right in line with the vids I scraped comments from. Doesn't matter, though, since no one is seeing it.

Now, I didn't expect a huge return on only subbing to other channels, but zero views returned and zerro subs returned after a week has me wondering if there is something that has changed about YT that is making this not work or if I am perhaps not utilizing this correctly.

Any thoughts?

its bit late to reply on this post but i really want to know if tubeassist is working for anyone here in 2015 ??
Kindly reply if anyone using it now.