Starts to wonder/starts wondering.

Hi. Please tell me... Are the sentences equally correct? Are they equally natural? If you had to pick one of the two versions of each, what would it be? Thank you.

She starts to wonder where her husband is./She starts wondering where her husband is.

The flashlight starts to flicker./The flashlight starts flickering.

He grabs an egg and starts to peel it./He grabs an egg and starts peeling it.