3 x Flute is definitely the way to go if you are routing binding or purfling channels on an instrument. Clean cut (at the right speed) in either direction. Prompt answers to my questions. Excellent customer service. Massive Thumbes up.
But the taxes, are a bit expensive.
3 Flute Rebate Set 3.5, 4.0, 4.5, 5.0, 5.5mm - 1/4" Shank
As a luthier I am using radian tools with confidence, they are performing up to my expectations, great stuff.
Excelent product, fast shipping