Geoff, regarding spare parts prices that I may query at times. I don't think that anyone can tell the difference between a 450 flex disc and a genuine 6.9 unit. Frankly, I would be surprised if 6.9 units are still available, in ORIGINAL guise. As I pointed out, I have 450 units, and I can fit them. No one would ever know that they are not 6.9 units.
Regards Styria
What is the difference between a 450 and a 6.9 flex disc Godfather?