This year we are using Linux via a desktop PC modified to fit within the rules. There is almost no latency if you use the programming port to communicate with the RC, and the only code we have on the RC is code to send input updates and receive output updates
(only 5 lines of code
(and a lookup table (It's dang fast))).
I feel that Linux is very important due to ease of use, support, and no vendor lock in. You can figure out how to do just about anything on Linux with only a good understanding of google, and most of the code you need for anything is already written in just about any language under the sun.