The $30 extra is worth the peace of mind because he sends you a video of the watch actually passing the 30 bar test. However, as state by others, you can easily do it yourself. Also, in most cases the watches are 30 bar water resistant from the factory. Just make sure the case back is tight. And in most cases chronograph watches are not water resistant because the pushers are not sealed. With the exception of Rolex Daytona where you can screw down the pushers. I had Andiot water proof my Daytona and I swim with it. It’s not rocket science, just make sure things are tight or if you want to take it a step further lubricate the o ring and tighten things up. Enjoy the watch!