Not sure where you're picking up on most AW girls now upping to £80 for 30 minutes........ having just done a quick check?
Still plenty at £50-£60 for 1/2 hour, and certainly the main reputable Agencies are still at that price range .
If I WAS investing £80...it'd be for 45 minutes with Delilah over at Premium, I'm still recovering from my meeting with her! Need to get over to see her agian, but bloody work is taking up all my time.