Ive read so many contradicting information online about these, does anyone have any good experience with these and are they worth the money?

and are their any really good ones?

I have been told that BMW now supply their own at about £10 a pop. I can't speak from experience as I don't run a diesel, the only comment I would make though is these things are supposed to keep the combustion cycle clean which they do by promoting a higher temperature burn clearing all the soot etc out.

If there is an underlying problem, worn injectors, low compression, low fuel pressure they wont help overdosing with additives can also cause a whole set of other issues.

One of my sons is a chemical engineer with BP he says as long as you don't overuse them you won't do any harm, he also says if your engine is in good order you may not see or feel any improvements either.

The independent BMW specialist by me sell Forte fuel/engine additive. It seems to have a fairly good reputation / reviews. It costs about £10-15 on amazon.

I just use Shell V-power diesel as it's basically diesel with the additive already added. I buy it regularly now the prices have been dropping. I find it slightly increases mpg and it says that it cleans engine components such as the fuel injectors.

Theres no harm from what i can see in using fuel additives with a BMW. Or just put some supreme diesel in. I always use either Esso or shell for my fuel. Just personal preference. Don't like going to supermarket petrol stations.