My company has this policy, but I won't use it for one very simple reason:
You have to agree to a clause that allows them to remote wipe your device.
If it was truly a work device, this would be fine as it's theirs to do with as they please. It's my responsibility to keep whatever personal information I need backed up in a safe place. I'd probably still have my own personal device for personal photos/email/music/etc.
For a device that I own and pay for, this is not acceptable.
If the work access was appropriately sandboxed such that they could wipe only, for example, an encrypted partition of the SD card where the apps are installed and store their data, then I might be on board. Companies consider their data valuable, but I consider mine valuable too. And just like they won't give me root access to their servers, I won't give them root access to my phone/tablet/pc either.