There are scam complaints with every (!) Forex broker and Instaforex is no exception. A lot of complaints come from trader that tried to abuse the Instaforex bonus program and got their account locked. This is a good reason and the broker has the right to do so. There’s no need to worry and you won’t have any issues if you don’t abuse their bonus program.
Some trader don’t like the fact that the Instaforex server seem to be a bit slowly if you try to scalpe. These are technical difficulties that occur rarely and not every trader experiences these problems. So no need to call Instaforex a scam.
There was a dispute between Instaforex and the Forexpeacearmy. You can read about here. Instaforex is not the only broker that rages against Forexpeacearmy and criticizes its behaviour. You have to judge it on your own what to think about this dispute.
All in all you have experiences that go both in the positive and negative direction. But you have to say that most of the negative reviews are not well founded. It’s not enough to call a forex broker a scam without the necessary evidence. So we can’t even call Instaforex not reliable until illegitmate practices are proven.