I have 20mm spacers all round but at a offset of +15 so the wheels are in line with the arch.
I went for the longer studs method as it is cheaper to be honest, and then 4 hubcentric spacers. Changing the studs over took some time but got there in the end, and it was well worth it.
Also steering does become a bit more sharp I think, and the wheels can wander when turning, but I think this is more due to having wide tyres on them (265 front and 285 rear)