RE: is the Latitude E5440 a good laptop ?
Not the keyboard issue as I don't use Linux on it and not the AC adapter boot, but seen others on here with those problems.
Sometimes I also get a flashing display when connected through a docking station and have to undock/dock to stop it.
Really hope you don't have any issues with yours otherwise you'll hate it! Even a 6 year old Acer I've got is more reliable.