As per phils post earlier on how to set the float valve, put a 8mm drill in between the float valve and hold it closed so it closes the valve,blow through the the pipe at the top of the float bowl lid and is there any sign of air passing through?
This is the only way to test if you have set the valve correctly.
Richard
Opinions are like people,everyone can be different.
Moss sell a ball type conversion that seems to have very good reviews.
I guess they are far less likely to wear long term, and presumably less likely to trap dirt, not being a taper.