I just commissioned a few of these drives. Here's my opinion:
What I liked:
Obviously the main selling point is the built-in Ethernet/IP. Even easier to set up than a PFlex 40 with a COMM-E card because you don't have to set up the COMM-E card in addition to the drive. I configured over RSLogix 5000 (I didn't and refuse to mess with Connected Components Workbench) and it was painless. Just pointed it to the drive and I was able to download/upload and change parameters.
The other thing I liked was the detachable control module that can be USB powered. This is great for plants that have a lot of drives and thus replace a lot of drives. When you plug it into your PC, it shows up as a USB storage device. On it is a PDF containing a parameter chart and a little app for uploading and downloading parameter files. Now, I should note you can ONLY upload and download this way. You cannot actually edit any parameters without Connected Components Workbench or RSLogix 5000 or by doing it the old fashioned way.
The parameters are a LOT different than the rest of the Powerflex family, but the scrolling LED display helps clear up a lot of mysteries. Instead of "F07" it actually tells you what the fault is. Very cool.
What I didn't like:
The control module is VERY difficult to remove. You feel like you're going to break the drive because it requires so much force to pull it off.
The control module still has the control wiring terminals on it. This makes no sense to me. The whole point of having the fancy, removable USB powered control module was so that you could give the drive to the maintenance guy and he could wire it up while you program it. It's "Here, take this and wire SOME of these wires up, and then I'll come and wire the rest up" instead of "here, take this and wire the drive up, and then I'll come in and plug the module in and we're good to go. I can't think of a single reason why ANY wires need to be on the control module. It almost negates any advantage to it at all.
The drive faults out whenever the safe torque off terminals are interrupted. And it's a non-recoverable fault so it can't be reset via Ethernet. I'm sure there were legal reasons for this, but what is the point in having an Ethernet drive if you still have to either go to it and physically reset it when someone hits the E-Stop or physically wire in a Reset button (if that would even work)?
Overall, I think this drive is a decent replacement for the 4/40 series. The good outweighs the bad and it's definitely worth switching to. But there are still some annoyances. I definitely wouldn't use the safe torque off unless the application needed it.