If your goal is to give outsider candidates who can't get as many votes as mainstream candidates the win, then no, IRV isn't going to work. But if your goal is to break the Duverger's Law spoilering problem a bit, to give third parties a chance to build up from small rather than their current direction of starting with President of the United States, IRV is good.

I've been living with IRV in Minneapolis for a couple of elections now, and what it's led to so far is tolerable, non-radical mayors. The most recent race was particularly interesting, as it took like five rounds to get a winner. I didn't vote for him, but he's been a much better mayor than I expected.