from: http://www.dailypost.co.uk/whats-on/everything-you-need-know-zip-12787158Daily Post said:The self-braking system and distance control system limits maximum speed and keeps the distance in between the sledges.
I was just about to post something on the matter. Most of the newer Wiegand coasters have the auto braking system installed to prevent crashes. As you can see, there is a small fin in the middle of the track in the video, which isn't present on the older models...from: http://www.dailypost.co.uk/whats-on/everything-you-need-know-zip-12787158
I'm taking that quote to mean there's an auto braking system in place for health and safety reasons. Max speed is supposedly around 25mph.
I think it's rather comparable to some of the European ones. But yeah, considering the (short) length, it's quite pricey...£15 for 3 rides is pretty cheap compared to US prices, but expensive compared to euro-prices. Go figure!