Looked at a number of EFBs over the past three years. There are some good products on the market, but ask yourself a number of questions before you part with your hard-earned.
1. Is it purely for TAPS? Or do you need flight docs as well?
2. Do you want it as a cheap moving map / mission planner? (insert any number of stand-alone GPS/NOTAM issues here..)
3. Area of coverage and ability to update when down-route
4. Purchase, upkeep & replacement costs
5. Do you want it to provide in-flight tracking with a feed to base?
6. Battery life vs ac power
7. Can it play minesweeper?
I think this is a growing market. I've got a whole load of brochures from Heli-Expo kicking around somewhere-PM me if you need any steers.