Yes. I don't know anyone that kept one. It cuts down your effective objective so deepens your depth of field.
Both leupold users I know that tried them had them off a week or so later.
In my opinion they are more a way of reducing the reflection a 3rd party may see off the lens not the people using it. If the effects on rangefinding aren't important then they are a lot shorter than sunshades.
BFTA/NSRA County Coach
CSFTA Chairman/BFTA Rep