A note of caution, if you have had the 998 recall done, the half-shaft straps might have to be modified to fit. Take a look on the VCA/My Gallery, I have a picture posted of the trimming I had to do to make the Unitrax straps work.
I have the BMR drive shaft strap and it is well thought out.
We put in 2 sets of the drive shaft safty loops with belly pans and they are great! It took some modifications to fit the Gen I vipers. It is too bad that you can barely see the bottom of the car with all installed. They look good.