There are many seven or eight-seat SUVs on the market today that you would presume you would be able to fit five child seats in, but as I have found in my testing this is not the case! Either the second row doesn't fit three child seats or the rear row doesn't have top tether points, or you can't access them without uninstalling the second-row child seats!!
Here is a list of all the seven and eight-seater SUV's, that I have reviewed so far, and found would fit five child seats in-
The Mazda CX-8 has FIVE top tether points?!! FANTASTIC!! They are all within plastic guides on the seat backs, apart from the central one in the second row which is right underneath the seat and I found I required an extension strap for the child seat. There are ISOfix points in the two outer second-row seats only and I found there was enough room for me to install three big child seats across the second row while using the ISOfix because there is plenty of space across the second-row seats, which is unusual and great! In the third row, I installed two big Britax child seats using the seat belts and top tethers, and there was ample room for them. The second row slides to adjust leg room and we found you could have a 184cm passenger sit in front and behind a rear-facing infant capsule. In both positions, there was 25cm of knee room which was impressive! The headroom in the third row was better than in the VW Tiguan Allspace but still only enough for the 184cm passenger to last a 30-minute journey before they wanted more space! For accessing the third row, the second-row seats slide forward and small kids could perhaps climb through but an adult could not reach through the gap to fasten buckles or bigger kids climb through without removing child seats. The second-row seatbacks are split 60:40 and the 60% is on the kerb side so you actually have to remove two child seats to access the third row from the kerb side of the car which seems biased to left-hand drive countries. I found that the third-row seats are very comfortable to sit in and I'm 162cm.
The Mazda CX-9 has FIVE top tether points?!! Yes! They are in all three central row seats and both third-row seats too! But the central seat's anchor point was strangely located slightly under the seat base and not clearly labelled, which didn't fill me with confidence when I was installing my child seat! There are ISOFix points in both the outer second-row seats, they are hidden in slits of the seat leather so you do have to line them up carefully and are not as simple as when they're within plastic guides. The second-row seat, behind the front passengers, has a folding mechanism that allows it to fold and move forward with a child seat installed (if using the ISO Fix, not the seatbelt) and gives a big step-through access to the third-row seats! I managed to very comfortably fit five large Britax child seats into the CX-9, still with plenty of legroom in the front for driver and 23cm of knee room for the front passenger! First, I put the Britax Platinum Pro in the third row and the rear-facing Britax Unity infant capsule and Britax Graphene (installed as rear facing) in the second-row outer seats and the Britax Kid Guard Pro booster seat in the central seat, there was plenty of space around the seats and installation was really simple.