Finally figured out what happened.. Switched Revo back to standard map, took it into the stealers to look at under warranty explaining the great loss of power, they did a software update. The car went better but not how a standard gti should be.
With Revo, there was a big difference in requested boost and actual boost so the car went into limp mode. When the stealer did a software update, it reset the limp mode so thats why it appeared to go better. However, some boost was still leaking which they didn't spot. Because boost on a standard map is not as high as Revo, the boost leak wasn't enough to put the car back into limp mode. So, got my tools to replace the DV,, guess what I found...




The car runs a treat now

just gotta vist Revo on Monday to get it re-Revo'd

So, if you boot it all the time and have a remap, this is what happens to your (well mine anyway) DV after 8k miles.
Will have to speak to stealer about warranty issues and Forge DV at some point..