A few things to add:
1.) Many people make the mistake of using a high velocity (285+) with the Flatline, this is not effective, the barrel works best at velocities as low as 265fps and as high as 285fps. However it will take personal testing with a chronograph to determine what velocity is best.
2.) There is a common myth going around that a Flatline breaks lots of paint at high rates of fire. THIS IS IN FACT FALSE! At high rates of fire the Flatline breaks just as little paint as any other decent barrel, with a good paint to barrel match and fresh paint this means not many breaks at all.
*This part is my personal opinion*
You do not need and should not use the shroud. It may look funny, but not using the shroud makes the Flatline a much more user friendly system.
Could we spell it correctly...please?
Take a look, you might be surprised.