with 8 mA mode NanoVNA has a little worse dynamic range for 0-300 MHz.
Here is my measurements for both cases taken on NanoVNA-Q firmware with enabled average mode.
The test case is the following:
1) enable average mode
2) calibrate
3) connect 50 ohm on both ports
4) take s2p file with enabled average mode
2mA.s2p - use 2 mA mode for 0-300 MHz (default NanoVNA mode)
8mA.s2p - use 8 mA mode for entire frequency bandwidth