If you really like the 'tablet' form factor, why not just pick up a cheap android tablet dedicated to just that application. You can pick up a new or (better quality) refurbished one for under $100. Opinions (and everybody seems to have one) differ, but if JUST for reading music on stage, I'm with you....I'd prefer a tablet as well, over a laptop or netbook. Lots of reasons; size, ergonomics, battery life (up to 10 hrs vs 2-3 hrs), weight, portability, and price. Just another opinion.

chas