Ive not heard of that one either im afraid...
The Japspeed K2 has had a lot of documented fitting issues. Ive got a Scorpion and so have a lot of other members on here, no one has ever complained about them. They are quite subtle in tone but a nice sound, depends how loud you want to go really. CS should be able to supply and fit one of these for under £500 if you wanted one.
Welcome to the forum btw