You are not going to get a real-world useful answer.
Remember, signal is not all or none. Though lower frequencies tend to penetrate better, amplitude/power intensity is important. The placement and power of your surrounding cell towers, the composition of the particular building/room you are in, other interferences play a role.
Short of a side-by-side comparison of the two devices at the same time in the exact locations(s) you will be using the devices, there are too many variables to give you useful information based on frequency alone.