Dude it doesn't matter if it is 27, 27.1 or 28! To activate the perspective view You just have to go to the hiden settings menu and switch on perspektive. This is exactly described in the V27 and/or V28 threads

For Your comfort ->
Enter the settings menu, press and hold the Menu button for 10 seconds, then scroll down to the bottom of the hiden menu, sellect Perspective and then Yes.

Timiboy