Full disclosure: I find the tech details a snore. It kept me away from professional photography for years prior to opening my doors. However, they are important to my art, so therefore I make it a priority.
One thing to remember about equipment - is the artist using it. A world class photographer makes iPhone pictures look professional. As long as there is back-up gear, who you are hiring is far more important than the equipment that they use.
Here is a description of the equipment that I use during the course of a wedding day.