Dont get a tablet unless you really want it. If you do get a tablet, you don't have to go with the school recommendation either as it is nothing but trouble.
Every student I have talked to said they only reason a tablet is it is handy for histo, but after that it is just a laptop and therefore get a computer you like and will want to use for a while. Check out the facebook group in my link for some disccusions on this topic.
Me, typically a pc person, will be getting a mac as I have now burned through three pc's two dell and one hp in undergrad, yet I see people still using macs with no or few issues to date that are older than all three of mine.
As to charging outlets, the two largest lecture halls do have available outlets as do the break-out rooms and therefore should never be an issue to charge.