I would think that using 87 in a M60 would actually cost you more as your power and mpg would drop significantly... and at the possible cost of trashing your injectors or engine.
You can try to run 87, but would go for a MobilExxon or Shell or etc... that uses good additives, but non additive 87 would ping like .
With most "chips", especially in a V8, I think they recommend 91 octane, so I'd be pretty scared using 87.
Current
2008 M5 6 Spd
2000 Z3 2.8 5 Spd MSport
2012 X5 35d Sport
1995 540i 6 Spd
1992 535i 5 Spd
Former
1995 530iA
1986 635CSI 5 Spd
2011 X3 2.8 MSport