I was recently involved in a project using one of these controllers. There are a few things you have to watch out for, especially if you are used to Allen Bradley PLCs. My application involved DeviceNet. Be especially careful as the Pro-Face controller is not the best Master device out there. They are a little short on support, also.
Overall the device worked pretty well, but there will be a learning curve. Some of the timers/counters work a little funny. For instance, to increment a counter you MUST use a one shot, if not it acts like a scan counter. The location of counter and timer done bits, and one shots, in the ladder logic are absolutely critical.
If at all possible, get one ahead of time so you can 'play' with it.
The last warning I have is if you download the documentation to the controller, a great feature, but it gobbles up controller memory. Also, if for some reason the system hiccups while you are on line, you will lose the documentation, so save frequently.
I would say this is a nice controller if you have a small application. I just happen to get stuck with what looked like a small application that turned out to be much more complicated than anyone thought.