I have a G21SF ambi mag release standard rail... I bought it a year and a half ago, and only shot it less than a 100 rounds. I see this gun about twice a year for a week at a time. But in 8 moths I will be a happy civilian again so I will see it alot more. I heard that the mag catch is a problem and will fail on me... Is this true? What would you do if it is?