Hi,
I've found this answer which states that the NUS throughput is around 2-4 kB/sec.
Really this is the maximum we can achieve? 1 Mbit/sec is 125 kB/sec. The 2-4 kB/sec is only 2-3% of it. It seems too much for the communication overheads.
Soft device: S132
Chip: nRF52832