Anyone ever rode at Swinley Forest, west of London? Their website makes it sound like they are a good year-round riding option, but anyone have experience riding there in the winter? We'll be in/around London for about 9 days, and was thinking of taking the train out there for a day of riding. They've got Marin rentals at the center on site. We're intermediates that are just starting to enjoy more technical riding, but wouldn't be bored by a couple hours of flowy singletrack in the middle of winter.