Some friends run a website with loads of information about rearfacing seats: www.rearfacing.co.uk and it didn't take long to persuade us that this was the right option for our two 1 year olds (the crash test videos are quite convincing...). We've ended up with the Britax 2 way seats, which are good if you don't have isofix, but do also have the extra tethers that Molly mentions. They don't have the leg though which is important if your car is like ours and has storage compartments in the passenger footwell. The only downside is that for some bizarre reason Britax won't sell them to UK retailers, so we had to get them from the in-car safety centre in Milton Keynes who import them back from Scandinavia! We went straight from the baby seats to these ones so J and T have only ever looked backwards, but they haven't grumbled yet. I would, however, recommend a mirror so you can see what they're up to!