It is up to the driver to know the capabilities of their vehicle, what it can or can't do, and to stay within those capabilities. The same vehicle may not be able to do the same with different drivers.

What does my passenger have to ofter that I may need, will make a difference as the whether they go or stay, room permitting. Another deciding factor is "Do I trust them" either with my life, vehicle or stuff.

Pre-planning is a must in my book. Know who you are willing to take well in advance, and establish guidelines/requirements on what they are to bring with them.