Success events on s.t or s.tl call?

Hello All, 

I am a bit confused as to which should be used to throw a success event, a s.t() or s.tl() call. This will fire on the confirmation page and originally I would have the event on the s.t (page view) call but hearing some recommend using s.tl call, would it matter which one is used when they both would contain the same variables (props/evars)? I was thinking keeping it in one call within the s.t() page view call to avoid a s.tl() call that could be combined on the page view call.

Tried looking on line for best practices and I know s.tl is for custom link tracking but what is the recommended or best practice for something like this?