Children should NOT sit in a front seat if it has an air bag at all because the air bag can KILL them in a crash....
its as simple as that (lots of publicity about car seats and air bags, not so much about children and air bags.... dont know why)
there for chidlren are safer in a lap strap in the back ratehr than an airbag front seat, cause although a lapstrap may cause internal injuries it wont kill them.
Many car seats that say they are suitable to be fitted with just a lap strap simply dont strap in tight enough.... so in the event of a crash the child sitting in the seat can be 'hurled forward more' which can cause neck spinal injuries, and therefore paralyse and kill the, WHICH IS WHY ITS SO IMPORTANT THAT CAR SEATS ARE STRAPPED IN PROPERLY (unfortunatly about 50% of car seats are NOT strapped in properly (which is frightening, esp as most mums 'think' they are))
One car seat that really DOES starp tightky into a lap strap is the Britax reinassance, because you strap it in tightly.... lock the seat belt, then use a lever to make it even tighter (so tighter thatn one could do themselves) so it IS held in tightly....
If you really WERE considering taking your child out of the childminders and 'wasting' £600, then maybe it would make mroe economic sense to purchase one of these seats (for about £100) and ask childminder to use that instead because it DOES safely strap in?
Just an idea?
I would NOT be happy with anyone travelling in a lap belt, tho i accept when thats all available it needs to be used, ratehr than no belt at all