I was using it for some time until they started to use all kind of tricks to force me to upgrade to the more expensive plans. It started from $5, then I was paying $10 and after the next "upgrade or we remove your account", I cancelled.
Wow, a bit surprised to hear that! What kind of tricks are we talking about? I've been on their $5 plan for over a year and have never heard anything from them about upgrading!
Interesting, they used to offer a 10GB plan for $5 (which I've always been on: http://d.pr/i/WDEK ) . Apparently it's not available anymore! However, I was never asked to upgrade my plan (I didn't even know the plan I was on didn't exist anymore before today!)
I was as well on the $5/month plan, I suspended my account for a little while due to exams, and tried re-activating it just to notice the $5 plan was gone. A few mails with support later they provided me a link to re-activate my 5$ plan. I didn't use it that much though, merely for shows in combination with showRSS.
I have had contact with the support of put.io more than once, and they were always very friendly and helpful. (even if some of the request were things such as "add play.fm support").
The big advantage over anything else I've seen with putio is that populair torrents are downloaded in a matter of seconds (due to someone else already having downloaded it) and the mp4-conversion. Btw, a small tip, instead of using the site itself for watching media which is downloaded, you can stream it directly into VLC or MPlayerX (the later also support streaming youtube video's I believe) which is very very handy!
Just noticed, there is an option for the legacy 10G $5/month account:
http://lry.be/WRxO