The eec-iv loom is completely different to the Weber Marelli loom. They do not need changing after 300 bhp, it's simply that until Motorsports Development undertook developing their conversion no one else bothered due to the complexity of doing so compared with using a Weber ecu. They run wasted spark as standard, I haven't heard of anti-lag on them though. TBH, if you already are running P8 then it's probably is not worth you converting because all your sensors and actuators would need changing too.