Narrow & Safe High Back Booster

[LittleRen]

Hey all... am due with our third baby (actually 4 days late). We bought a Q7 in April as it's big, practical etc etc and assumed we'd be ok for three children in the back. In our usual laid back style we finally decided to try the car seats... they fit quite well but it's going to be really tough to fasten the seatbelts without a struggle every time.

Can anyone recommend a slim but safe high back booster? Currently we have a Cabriofix for baby on a base, Diono Monterery HBB in the middle and Recaro Monza on the other side with an impact shield. All Isofix but if the new booster isn't isofix I wouldn't be too concerned.

The booster is for my 4.5 year old, he is tall but I would rather not put him in a backless if I can avoid it. Of course he could go in the front or the third row but ideally I wanted to keep front free for now, same with the boot.

I have found this one.. www.tesco.com/direct/graco-junior-high-back-booster-car-seat-without-harness-group-2-3-dove-grey/756-5461.prd?skuId=756-5461&pageLevel=sku&sc_cmp=ppcPX+-+NurseryPX+-+Shopping+GSC+-+Nursery+GenericPRODUCT+GROUP756-5461&gclid=Cj0KCQiAnOzSBRDGARIsAL-mUB2oejkctXVwpzPX98bCZZki8LWAMvZo5J3jVw3J1JVWj810Q4TMFAIaApj9EALw_wcB&gclsrc=aw.ds&dclid=CK3E8bOG2NgCFdGCGQodgO8CXA but it just isn't what I am used to seeing, big padded booster seats!!

Anyone got any suggestions? Thank you!!

We use britax adventure. It is very narrow. Just brought the second one.
I think is also rated as safer than the one on the link you attached.
It sounds like you have 3 full seats so I think you should be fine but may be stop by halfords or carseat fitting place for advise. When I was looking for new car seat before the arrival of the 3rd baby I was advised that if I put 3 seats on the back seat I will creat a "brace". In case of side collision my middle car seat will be ejected! But my car is smaller thank yours. I solved the problem by putting the 7 year old in front with disabled air bag. When we are all in the car with my dh driving I sit in the middle back seat. Not ideal but works for now, our next car will be a 7 seater.