At first, sex will damage the surgery as it still needs to heal. Once you are cleared for sex, sex will replace a dilation. The trade off is if your guy is undersized it would be desirable to use some dilatation to maintain your size over the first year or two. Others have gone only with undersized sex and when the relationship broke up, they needed dilation to return to normal size.
I am very post surgical and went 10 years without dilation. When I returned to it, things were rather tight and I walked a little funny after the first few sessions but I have regained what I lost. Monitor yourself carefully to figure out what you can and can't do as regaining what you lost can be time consuming and a little painful.