Integrated child seats in the fund seats at the XC70

Hello. Our family is about to buy an XC70 MJ 2016. Now I would be interested in your opinion about the integrated child seats in the fund seats (family package) regarding safety. Are the integrated child seats as safe as a child seat fixed with Isofix? What do your children say about the comfort of the integrated child seats? Our son is 7 years and 125 cm tall. Thank you for hopefully many answers.