In the diagram below, the 42" panel is depicted by the dotted line and the 48" panel is depicted by the solid line.
Due to the 6" of added depth, you can see that the slope leading to the hopper (deep end) is more gradual than in a 42" wall pool. Therefore, the 48” panel provides a safer diving pool by providing additional space for a diver to arc and surface with less risk of running into the bottom of the pool.
KEEP IN MIND
While the panels are 42” and 48” in length, this will not be the final depth of your shallow end. Keep in mind that 2” of those panels will be covered by your pool base pre-mix and your water line typically falls between 4-6 inches below the top of your panel. Therefore, your shallow end’s final depth will be as follows:
Overall, there is no right or wrong answer when choosing the size of your wall panels. Below is a diagram that may help you make the best decision based off of what you need out of your pool!