Sealed battery disadvantages (need to know asap)

I need to know all the possible disadvantages of a sealed, non-removable battery. I actually don't intend to use the notebook unplugged, so even if the battery dies it would not be an issue for me. That said, can a sealed "dead" battery harm the notebook in any way? Would I be able to use the notebook plugged in without problems? Is there anything important I should be aware of?

I want to buy a notebook which has the specs I'm looking for as well as positive reviews, and literally the only thing that makes me think twice about it is this sealed battery thing, as I've never had such a notebook before. That's why I wanted to ask the experts here about all the disadvantages.

The only thing I can personally think of is if a liquid is spilled on the machine one wouldn't be able to remove the battery. But aside from that, is a sealed battery in any way problematic for someone like me who intends to use the notebook always plugged in?

Here's the notebook in question: http://www.notebookcheck.net/Asus-N752VX-GC131T-Notebook-Review.161407.0.html

Intended use is CAD, 3D, and some not overly complex video editing. If you think this is not a good choice, please elaborate. Budget is € 1200 and this one is slightly above it which is OK.

Fast replies would be much appreciated, as I intend to buy the notebook tomorrow or Friday the latest.

Thank you all!