I dont know about vac motorsports. But the recaro one allows you to use the original seat belt receptacle that was on your stock seat. That way you still have access to the ... explosive buckle that (correct me if i am wrong) ejects the seat belt after a crash in case you get stuck or something along those lines! lol.
But i didnt go for VAC because you couldnt use the original seat belt receptacles.
Current: 14' 435i M Sport: Cold Weather Pkg, Tech Pkg, Premium Pkg, Driver Assist Pkg, Lighting Pkg, Dynamic Handling Pkg, M Brakes, HK Sound.
PAST: 09' 335i (Beast), 09' Z4 30i, 09' 328xDrive, 11' Camaro 2SS, 05' M3, 11' Mustang GT 5.0, 09' ML350, 07' RS4, 08' X5 48i, 07' Cayman, 11' 335i xDrive