In the publication below [1] a comparison with respect to latency is made between Teensy, Arduino Uno, xOSC, Bela, Raspberry PI and xOSC. One of the findings is that serial over USB is slower than Midi over USB while technically very similar.
The Axoloti [2] is not included in the publication but is of interest as well when building low latency audio devices.<p>[1] <a href="http://www.eecs.qmul.ac.uk/~andrewm/mcpherson_nime2016.pdf" rel="nofollow">http://www.eecs.qmul.ac.uk/~andrewm/mcpherson_nime2016.pdf</a><p>[2] <a href="http://www.axoloti.com/" rel="nofollow">http://www.axoloti.com/</a>