I'm taking a UK domestic flight with two children 3.5 and 5. They're both just over 18kgs - the 3.5 year old is a heavy chap.
I'm debating whether to get trunki boostapaks for the hire car, or renting car seats from the hire car company. Concern with the boostapaks is 3.5 year old is in a five point harness seat still and not sure I can trust him to sit still.
Does anyone have any experience of rented car seats in terms of quality etc? The drive is about 1.5 hours if that makes any difference. Would welcome experiences of both, thank you!