Yes, going there this weekend. Had initially downloaded their fees & charges .pdf from the website, and on the basis of my aircraft/pax, it was going to be more than that...so when I phoned up to get an answer, on being told it was a flat £45 my first thought was "ah, that's good".
Then that thought was swiftly followed by another, much louder "No, it's bloody not!".
Pity Hethel is a Lotus test track.