Engine Oil Additive

Has anyone used an engine oil additive, such as greased lightning?  I put it into my modern 1.8T VW engine and I felt it made a difference, but have been reading that there have been a lot of problems with it clogging filters.  Anyone tried it in their Golf?

don't do it completely pointless. use a decent grade oil from a reputable manufacturer.
said it before i'll say it again. billions of pounds go it developing oils to do the best for a engine (no cuts to make it not last very long or any other cost cutting) the oil will have all the additives an engine requires.

on the other hand millions go into developing oil additives (note millions not billions) that make your engine run smoother etc etc etc. these additives can and do interfere with the additives in a decent oil.

if your really worried about oil stick some flush in then change the oil but to be honest just using a decent oil will do all you need.

synthetic or semi synthetic castol, valvoline or mobil will be more then good enough. (and there all made in the same place)

Other thing to help is to take off the sump - clean old the gunge off the bottom and put sump back on. Then use decent oil and change every 5000 miles - your engine will love you for it!