If you use silicone (dot5) you need to absolutly sure that all of the rubber components are compatible with it. Most automotive brake system rubber parts are intended for use with glycol based fluid only (dot 3, 4, 5.1). Incompatability can lead to failure of the brake system. As long as the parts are compatible with dot 5, there shouldn't be any problems using it.
My personal opinion is to use what the vehicle calls for. This comes from my own experience with dot 5. I jumped on the dot 5 bandwagon after reading about how it doesn't hold moisture and was good for older vehicles. I used it in the '55 when I rebuilt the brakes, all new hydraulics and rubber parts. It performed alring, pedal feel was decent. Then I started noticing a small puddle under the truck that wasn't oil. turned out the silicone fluid was not compatible with the rubber in my brake system, causing it to leak. I contacted the manufacturer, they informed me that none of their automotive brake parts are dot 5 approved. After changing out the rubber parts and installing dot 3, no problems since. To my knowlege, the only company that made dot 5 compatible parts was EIS, who is no longer in business.
