I've had the Fat Cat 2:1 on for a little over a week now. Work has not allowed me much ride time since they were installed. They are definitely much louder than stock. But, as buxndos says, the pipe length on my FLHRCI puts most of the sound out behind me. I beleive they have a shorter pipe to be used on non-bagger bikes. I'm really pretty conservative and don't find the volume to be overwhelming. The note is good. It may not be as deep as some others. More of a tenor than a bass. It really hammers when you roll the throttle hard. It is not have the 'crack' I've heard with some others. I like the Fat Cat sound better. I've promised to post some pics. A buddy borrowed my digital camera for a project last week. Maybe I'll get it back this week. I don't understand the out-of-stock issue. I took my bike in one afternnon with no notice and it was ready the next afternoon. I know the company is located here in Fort Worth. But, still, available is available. I have experienced some gurgling - almost popping on deceleration. I had a stage one done when the pipes were installed. I may need some additional tuning. It seems the idle is faster than it used to be.