Cost about £55 for the large 5 litre bottle of the Genuine Mercedes Benz oil specifically for the 722.6 although they also come in smaller 1 litre bottles. If you purchase the oil from MB dealership, you get a MB receipt which you can keep in your service book. They do occasionally pop up on ebay though haven't seen it that much cheaper. The oil is pink in colour to start with and smells like sweet/ester. As it degrades it turns to brown colour and then smells like burnt smell, that's when you get problems i.e. slippage on a cold morning.
thanks chaps - never seen that Comma stuff before cos it didnt pop up when I searched +4 .... presumably due to it being a multi spec fluid. I'm going to get 2 & re-do the change a few days after the first to dilute the stuff still in the TC. It'll be a suction job - I see no great purpose in the crappy filter. My car has 54000 on the clock & shows no problems changing etc, but I'm starting to detect an underlying 'milkfloat' noise
Don't worry, you just need a bit of confidence. If your using the suction method, you can withdraw a little out if overfilled. Still think you should do the filter though at 60K with MB receipts for peace of mind.