Has anybody tried Twitter ads yet?

I have done a couple tests and it seems to work fairly ok.

Things I've noticed: Use different copy then you use on your other social networks because it is a different audience. Also use images, they increase your chances of getting people to act on your tweet.

Also heard that if you ask people to retweet with '#RETWEET,' it increases your chances of getting one by like 100%. Haven't tried this yet though.

But I wanted to know, has anybody else used them?

Automatic 3k - 4k follow on Twitter Is there anything I can do?
pm please.