Leo got the iPhone 12 Pro Max and he says it's HEAVY. It also has a larger screen for plenty of room. The pixels are larger, too, so he gets better low light performance with the three-lens camera. Leo also says that the camera "bump" is pretty prominent, as well. Leo also says that could cause the camera lenses to scratch over time because the phone will rest on the bump.
How is 5G? Leo doesn't know because it isn't available everywhere, and where it is, it's likely the low band 5G, which is about as fast as LTE.