PaulS:
Should I have it setup like this: if(mySerial.available() >3)...making sure there's 4bytes in the buffer? Or is that no good either?
That's better, but still not perfect. I'll try to explain why. Reading and acting on 4 values read from the serial port is fine, up to a point. Suppose that the serial buffer contains 'L', 120, 34, 95, 'R', 14, 126, 240. Now, if you test that there are 4 or more bytes, and read the first 4 bytes, you have all the data needed to control one LED, and you know which one to ...
hmm, I see what your saying, thank you for the detailed explanation. Will flushing the buffer and changing the baud rate help if I choose to send bytes?