This is good advice. Also, if you have to get a spot from someone you don't know and trust, be sure to communicate exactly what it is you want from them and how you want them to spot you. I hate it when a spotter keeps their hands on the bar from the first rep; even if they say they're not helping, I can't really be sure, and it throws my rhythm off for the whole set, not to mention it makes me wonder exactly how much of the set I actually did myself. I also like to tell them exactly how to spot me if I need help; let your spotter know if you want them to immediately lift the weight completely and help you rack it, or if you just want them to provide the minimal amount of help needed to finish the rep, and if you want help doing any additional forced reps. I occasionally get stuck in a rep, or move the bar very very slowly, but can finish the rep, so I may tell my spotter not to touch the bar unless I tell them to or they see the bar move downwards. A spotter can only be as good as what you tell them you want.
I agree that having a spotter gives one additional confidence, but I also find having a spotter to help me with the lift-off allows me to get in better position, especially with my shoulder blades, than if I had to reach back and un-rack the bar myself, and I consistently can get an extra rep or two when I have a good spotter.