I paid for a year. They just totally shut up shop, didn't develop a feature, didn't do a thing. I left after my year's subscription was up, sick of sticking up for them in forums/reddit etc and realising most of the complaints people were leveling and them (him?) were valid.
It's a shame to see Google treat anyone like this, but meh, that's how we felt after paying up for Pushbullet Pro which saw zero development/love after the fact and the developers who had, previously, been very vocal and supportive, go to radio silence.
I kinda support Google here, put this poor thing out of its misery.
1: https://www.reddit.com/r/PushBullet/comments/6wby5b/is_pushb...
2: https://www.reddit.com/r/PushBullet/comments/7bjvhx/is_this_...
3: https://www.reddit.com/r/PushBullet/comments/77egnz/is_pushb...