[Radoye]

The Me-262A1/U1 had a mix of 103s, 108s, and 151s. Having different ballistics can round out a volley, especially at mid-ranges (ie. a 103 provide central accuracy, 108s provide rate of fire).

Yes, but that's done as an experiment, because the 108-only armament was found inadequate due to the low muzzle velocity (can't consistently hit agile fighters because the guns aren't accurate enough under high deflection angles) so they tried to mount different guns. 103's only were out of question due to excess size & weight and low RoF and 151/20's only were too weak so they mixed it up. So this was more born out of a necessity than because they though it was a good idea to mix armament types...