Life is all about personal choice, decide the factors and it makes the decision. I have the taller hoops. My decision was based on sitting in a car with normal hoops and realising that the top of the hoop would smack you square in the centre of the back of your head in the event of a shunt. they are supposed to be there to reduce whiplash - with the standard hoops I think whiplash would be the least of your worries! Its not possible to rest your head on them - even wearing a helmet.
The cover sits in front of them so only a car cover might not fit - never been a great fan of car covers as they don't always allow a damp car to dry.
They don't really cause a blind spot in my experience, but everyone is different. Sit in one and see if the restricted vision of the taller ones is a bigger issue than the potential injury from the low ones
