Characteristic write value time highly variable across machines

[alonks]

I'm communicating with some Sphero robots for a project with this library, and I am finding that the time it takes for a characteristic write_value call to get to the write_value succeeded is ~.01 seconds on one Linux machine, and ~.1 on another.

This is at the same distance to the robot. Anything that might explain the variability? Not sure where to start looking.