new car seat - isofix or seat belt ones?

[teacakes]

DD is ready for her next grp of car seats (10.5 mths)

Is it important to get a car seat with isofix or one for normal seat belts?

Are isofix that much safer? We are thinking of getting a second car and isofix seems to be rare for older cars.

Isofix seats are great if you have Isofix in the car already, but the best belted seatbelts are as safe as an Isofix one if properly installed, so don't go mad hunting an Isofix car.
(Remember car seat groups go by weight not age)

isofix are brilliant and can still be attached using the seat belt if one of your cars does not have isofix.

Check the seat you want to use them is has isofix - i got one for ds3 hoping to put him in the middle seat only to discover that it only works on the outside seats.

If your car has ISOFIX, get an ISOFIX one, much safer than a seatbelt one. Now... if the car doesn't have it... there's no use of getting an ISOFIX carseat, as you can't use the function.

Second Isofix, but only if the car has the facility otherwise not much point. Better off buying another Which recommendation. And to be honest I tried my Isofix car seats with a seatbelt and they were not very stable.

Never heard of them, what are they?

It's a system whereby the car seats fix directly onto the car chassis through metal brackets. Sort of plug and go. No need to mess around with seatbelts. Called LATCH over in the States. It's great