Osrry if this doesn't make sense but been reading about rear facing until 4 etc. and have found this which was on the rearfacing website but it says here than it turns to forward facing at group 1 stage. Is that just an option though? Does it mean you can leave it rear facing until 4? Thanks
I'm not sure if you've linked to the seat you intended to link to! The BeSafe Izi Comfort is a forward facing Grp 1 seat - it can only be used forward facing.
BeSafe also make two other seats that cover the Grp 1 weight range: the Izi Kid and the Izi Combi. Of these, both can be used RF over the entire weight range (0-18kg), but the Izi Combi can be turned forwasrd facing for Grp 1 if you would prefer.
You need to check for each car seat, though, as some of the RF/FF Grp 0/1 seats on the market (such as the Britax 1st Class and the Concorde Ultimax) have only been tested RF till the end of Grp 1 and as such should not be used RF beyond this point.
As far as i can work out, in a group 0/1 car seat you can keep them rear facing for as long as their feet don't start to be pushed against the back of the seat. At some point there isn't room for their legs to fit! Nania Driver SP and Maxim SP are group 0/1 so could be worth looking at and seem very good value. here
The Britax First Class can be rearward facing up to 13 kg or just over 28lb which could be up to two years of age (depending on size the child). I would stay away from the nania as we have had loads returned in store and have since stopped selling them the quality is poor compared to Britax.