Really? XenForo has had that add-on since 2012, and I believe it is similar to one that was out for vB prior to that. PostRatings is one of the most sought after style add-ons for other scripts (hell, look at how long it to IPS to get similar to an add-on). And I'm fairly familiar with best 3 of them. I have licensed Burning Board, IPS and XenForo sites and I am regular participant on all their support boards.
It's long overdue that IPS got a similar add-on.
I guess you think because it "costs more" it's always better. There is a word for folks like that used by sales people. It's called a sucker.