4-2-1 is different to the 4-1. 4-2-1 isn't made anymore but is said to have produced more torque - whether or not that is true I don't care, I just wanted 4-2-1 as it is quite rare and hard to find
All new milteks are 4-1. If you want it quiter keep the cat and get a resonated system though!! Non Res + decat is quite...loud
Where abouts are you from? is St. Neots far from you?