yes you may drive your car to iva as long as you have insurance. infact you can drive your car to any pre booked ministry of transport appointment with just insurance.
my iva centre is about 10 miles from me but if i go there through the lanes its about 11 miles but i will have more chances to use the brakes and get them bedded in. if it breaks down on the way then i will just go get the trailer
it had a whole day of being hammered on the rolling road and didn't miss a beat once so im quite confident that it will make it.