Got one myself Tim, They're awesome!
It even goes in my lightweight kit as a luxury item. Tried all sorts of chairs from sit pads to stools etc and they are good for short periods but if chilling out for long periods they get on my nerves. The Mayfly is really comfy and has back support. Only problem though is getting in and out as it's low to ground but I just try and pack everything I need around me lol.