My money is on the serengeti's. I brought a pair off ebay about 6 months ago. I liked them so much that I went back and got another pair as a spare just last week. They have the drivers gradient and photochromatic lenses. Think they are a year or so out of date but from what I can see look about the same compared to the current models and its not a fashion show afterall. The model I got was the Pergusa and checking ebay this morning they look to be 55 quid. Very comfortable to wear and they brighten up conditions when in IMC no end.
Do a search on ebay.co.uk. The guy selling them is a powerseller and the glasses arrived in the next days post.