It's a relatively clean runway surface mate so much better than an airfield but nowhere near Snetterton's level of prep. The areas of the track that criss-cross over the runway is more abrasive and this is where you may pick some small stones up. I've driven everything from the mk2 white, the mk2 black and the M3 there. I even took the mk2 white back and Ben and I gangbanged it!!! If you are fairly open minded about tyre destruction you can get an incredible amount of laps under your belt and this is the main 'issue' with the event. You can almost get too much track time! It's the longest back straight I have ever seen and I would expect that you'd get 140+ out of the Cupra there. If you allow plenty of time for cooling purposes you should have no real dramas at all.
The event is run with real precision in terms of infrastructure. The catering is great and the atmosphere is very relaxed. Some of the posh boys don't like getting a NATO M3 fired up the inside of them

but generally they are very accepting of 'differing' levels of commitment
I reckon Marham has to be done at least once. It is cheap, it is fucked up fast and it is a real laugh. Add in to that the great cause it supports and the variety of cars there and it quickly becomes an essential part of the calender.