I would avoid the Windoz based strictly on that all Windoz systems are more vulnerable to viri/hacks/etc.
The android tablets we have are generally safe, we got an MS-Office compatible ap for them from the Google-store.
I haven't used an iPad, but Apple tends to keep their OS locked down well enough the vulnerability should be low. I would be very surprised if there is not MS-Office compatible ap for iOS (but I have never looked either)
2008 F350SD V10 with an 2012 Arctic Fox 29-5E
When someone tells you to buy the same rig they own, listen, they might be right. When they tell you to buy a different rig then they own, really pay attention, they probably know something you don't.