Fantastic active monitor speakers that sound great and make you feel right at home.
A couple of issues and tips I have noticed on these are:
watch out for overheating resistors in the power supply (R2, R3 and R17). They cause damage due to the heat travelling up the board, look at the pictures for the smoke damage on this (working board). They need to be removed from the PCM cleaned and re-soldered to improve conductivity and ventillation.
When replacing the output devices it is critically important to use matched devices, otherwise they will fail usually within the first hours use. Matching does not take too long using the Nelson Pass method but remember to allow two minutes for each device to warm up a little before taking a reading. You need a stock of about 20 devices to get a good set of matches.