McCallum plastic pipe chanters are a huge success. They are easy to reed, bright and stable and give good volume.
As they are made by pipers for pipers they have put a light thread in the reed seat of the chanter which overcomes the problem of reeds coming loose. The thread means the reed is locked in place and connot move unless the piper moves it.
You turn clockwise to sharpen the reed, and anti-clockwise to flatten it. It’s also a much more accurate way of setting the chanter reed.