Have an ipad 3 WIFI+Verizon LTE. Was jailbroken on ios 6.1.x IIRC. Started looking and really, other than the mail notifications icon in the tray and color mail labels, all my tweaks were either now incorporated in some way or were just not that important (I do kind of miss color mail labels since I have three email accounts, but that's it) I did an upgrade on top of the JB ios and have no issues at all.
I have an iphone 5 for work and one as a personal phone. The work one came with ios 7 and after using it a few days, I decided to upgrade the ipad. I am teetering on whether to upgrade my personal phone to ios 7 also. If it were jailbroken it would be a no brainer of course, but honestly, I think I can deal with it.