Vossen's are crap. I couldn't believe the horrendous build quality when I was looking at their display wheels at the LA Auto show. Paint runs, jagged edges on the backs of the spokes, etc. My vote = neither.
2008 IB E92 M3| BBS | KW | Arkym | Platte Forme A.G. | Active Autowerke | K&N | Fabspeed | Dinan | Evolve-R