Some manufacturers put a special coating on the throttle body to resist deposits. On those designs you have to use a special "throttle body cleaner" now sold in many auto supply houses, since regular carb cleaner is too aggressive and can remove the coating. This is probably the basis of conflict you've been hearing.

I have seen no such warning on my 95 E320 or in the manual. So I can assume you can use regular carb cleaner for your car.

When cleaning, use solvent and a toothbrush. The stuff doesn't just "melt" away--- you really have to work at it. Clean the bore ID surface and the butterfly valve edge. When finished you should have a clear, even gap between the valve and bore.

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95 E320 Cabriolet, 159K