Well I've just replaced the lower engine mount for the new modified Powerflex Yellow one. I had previously replaced the OEM mount with the Powerflex Red mount. It lasted 8 months, and about 8000 miles before going into breakup mode 
I have only driven a couple of hundred yards, so cannot comment much on the modified mount, but it does seem to vibrate a bit more, but will comment after driving it for a sensible distance.
Just so you can see how it broke, here's a picture of the cream crackered mount:


I have only driven a couple of hundred yards, so cannot comment much on the modified mount, but it does seem to vibrate a bit more, but will comment after driving it for a sensible distance.
Just so you can see how it broke, here's a picture of the cream crackered mount:

Richard