car seat covers (dangerous?)

I want to buy this for my sons car seat. I was wondering if it would effect the safety? I cant find anything online. When I brought him home from the hospital they told me not to use the strap pads or the extra head padding on his car seat bcuz it effected the way the straps fit him. And that it wasnt crash tested. but would this be the same since its just a cover? It shouldnt effect the way the straps fit around him right?

I'm pretty sure that anything after-market voids the warranty of the carseat. I probably wouldn't...

It does effect it. The car seat is not tested with the cover on it. I wouldn't do it.

Anything that isn't made by the manufacturer voids the warranty and is considered dangerous.

The same goes for toys, straps, strap covers, and the neck thing.

ok thanks ladies. I guess I shouldve listened to myself from the beginning lol been debating this for a few months now