I love my new Epic 4G... Awesome phone, but being a smart phone with 4G and all the goodies, if I leave everything on (Bluetooth, GPS, Wifi, 4G), at the end of the day, the battery is dead.
Never had to yet, but someone once told me they charge you $10 extra to be able to do that.
I turned it on just once to see if it was blocked and it was not, but didn't have anyone actually trying to use my phone as hotspot for that brief moment.
I'll give it another shot sometime and will let you know if it works.
I have the sprint evo and its a great phone, sprint is all I have ever used and they seem the cheapest/best coverage. Free roaming onto verizon's voice network as well.