the overall price difference is minimal, and the benefit is great.
If you are doing this yourself, (I hope not) then PLEASE BE CAREFUL and don't do it alone. Always have someone else in the room with you as you work. Make sure you have the power locked out while you make the change. Have lots of batteries on hand to power your lights with. You may need to have a permit, and I definately recommend an approval inspection for your new box, before you reconnect, so that someone who KNOWS what they're looking at can assure you that you did it right and your house won't burn down.