I used a Bosal on one of my 77 cars, and it worked great and was still muffling well when the car quit five years after installation.
It's a bit throatier, but a very nice sound. It's not noticable in the car as long as you make sure the exhaust tip extends just past the bumper. The reason most e12's are exhaust pipe noisy inside the car is when the tip falls short of the back edge of the bumper.
Yes I did; a mechanic (then at the dealership, now independent owner, who almost bought my car before I did) told me that and recommended to use 7 series tips which are longer, just for that reason.
