I recently swapped mine for the M16 silenced, but before that I was using the Tar with heartbeat and silencer. With cold blooded pro and ninja pro on it's an awesome gun. I found it was a bit too rubbish at long range though, hence switching to the M16. But my favourite tactic is used on search and destroy, basically you keep tapping the switch weapons button while prone near the bomb, let the enemy arm it, crawl up behind them and then disarm it the moment it's planted. Unless you play against people who use the tactic or know about it already most people won't spot you and you get an instant ninja defuse.