Great tip !When you buy the filter use the one that is fleece not paper as it is the upgrade to the paper type. Also use the recommended 0 W 40 Mobil 1 motor oil you can get cheap at Walmart in the 5 qt jugs. As a technician for 38 yrs the only lifter noise additive I have ever seen actually work was from Napa I think it was called Valve Clean in a black bottle about 12 oz.
Now I will tell you what nobody else here has mentioned. Mercedes Benz mechanics will usually take the vehicle with a warmed up engine and drive it in low or second gear for up to 5 mins @ 4500-5000 rpm watching the temp gauge. If the temp starts to go past 100 stop the rev conditioning and drive the vehicle for a mile like normal. This usually purges the lifters and the noise will go away. If this dosnt work proceed with the oil change. And if possible refrain from using additives as it is not recommended. The reason for running the engine at such high revs is that your valve train rpm runs at 1/2 the engine rpm. So you have to rev it up to pump up the lifters and purge the lifter galley and lifters. I hope this works for you. If this and the oil change do not work you will need to inspect the camshaft and lifters. If you can identify the exact lifter making the noise you can get away with replacing the affected lifter only. Be sure to order the correct lifter as some models require a different part number for the intake and exhaust. Good Luck!