I went for that one in the early eighties. It is not a good idea. True, the DOT-5 stuff doesn't absorb moisture. But the moisture is still there...usually in concentrated little drops that start to eat away at the metal lines from the inside. Nevermind the goofy pedal-feel you get with it. Learn from the mistakes of others...just don't use that stuff. The DOT-4 fluid is more than enough.
Regards,
Randy D.