Personally, I dont really see the problem with a mixed allocation on a Sapphire route. It already occurs on routes including the 6, 7 and 24 and thats a bigger difference with Pulsar and E400 compared to E400 and E400 MMC which is possible at Ashington. As long as the vehicles all have the same spec then the majority of passengers wont notice the difference. Either way though those 57 reg E400 need replacing soon.