The million dollar question 4 years iv looked for the answer on and off and frankly there is not a single person on the planet who can answer "what the shock difference is" i even have a sachs catalogue from 2003 and the the msport 2 and msport 1 shock have an identical part no.

Through searching iv also found msport 1 shocks for £80 sterling directly from sachs

Arb difference is 1mm between the pair on the front cant remember the rears off the top of my head