20% all around you can't go wrong! I had the same dillema as you and I don't regret at all with going 20% everywhere.
35% wont save you a ticket so might as well go 20%
2011 E92 ///M3 6MT - Alpine White / Fox Red
ADV.1 Track Function - PSS - lots more to come...
Retired: E92 335xi Msport FBO - Lemans Blue
Retired: E92 335i - Alpine White