ST sway bars?

I know upgrading the rear sway bar to a 19mm st bar is good. But I’m wondering is it worth it to change the front sway to an st also? I know a guy selling both as a combo. But its cheaper just to buy the rear by itself online. I just need to know if there is any benefit to switching out the front.

I have them both and love them.

I have then both and also love them. I was told by having them both I would have to worry about under steer but I have not had a issue since I was told that.