Once you use correct fitment spacers and make sure they are hubcentric then you should have no problem. Most people use option 1 method which is the bolt on spacer which bolts onto your existing studs and then your spacer bolts onto the spacer. For 10mm spacers this method wont work as they do not supply then this small. If you have the standard wheels or rays you can have max 20mm front and 25mm rear.
However, a few people, like me go for the second option which works out cheaper, where you replace the original studs with longer ones, and then slip the hubcentric spacer on and then bolt on the wheel like normal.
The safer option I dont know. I would day both methods are safe once using quality spacers which are hubcentric.