I have recently learned that open front jump boots are not good for going cross country. I understand why but my sister has just bought a new pair of open fronts she plans on using for eventing. I told her the new info i learned but she doesn't think that it will make a difference because she will only be jumping between 2 foot and 2 6. Will her horse be okay in this sized jump with open fronts or should i really try to convince her to get full coverage boots? Thanks!