Yeah it is, but they can come out i guess if you have a big impact.
Adrian is correct that as it comes it is a good solution. It's kind of funny why i started running without it. When i had an Mi2 proto car, i got it without a strap, so had to use one of my own mission ones. However the strap is actually "upside down" compared to the mission, so i had to pop the spine out - and hence have never bothered running it since!!
btw, Chris P - just noticed that your car hasn't got purple Alloy nuts. Shocking
