Save your money and buy the best car seat you can afford. A good car seat will be still strapped in place with a crying infant/toddler while the rest of the car is destroyed. Air bags won’t really do any good to protect your child while they are strapped into a car seat. The car seat stays with the seat it’s tied down to and it has its own side protection etc to protect your precious cargo. In 5 years when (s)he graduates to sitting a booster seat, then buy a newer car with advanced occupant protection (likely to be a big step up from today even) and get 10-15 years out of that one.
Congratulations.