Been using the Esso 99 since it came out maybe a couple of months back. Feels better to me than the Shell 99 stuff, and definitely more responsive than the regular fuel. Worth the extra to me as my standard MK5 GTI feels more powerful and get a few extra MPG with it. Tesco 99 is more expensive round my way and supposedly isn't as good as the Esso and Shell.
And the reason it says ethanol free and up to 5% ethanol is because it is ethanol free "except, due to technical supply reasons, in Devon, Cornwall, North Wales, North England and Scotland"
Wacked some E10 in it a couple of weeks back just to try it, and it developed a misfire on cylinder one between 2000-3000rpm. Probably was a coincidence but I was dreading having to replace the injector, as I had read the higher ethanol content can free gunk from the fuel lines to them. Ending up replacing the spark plugs and single coil on cylinder one and thankfully it went away. I've tried the E10 since and it ran fine but prefer the 99 Ron stuff for sure.