Customize it does very well, so had nothing to cut away from Macbook or even from the battery.
The nub of plastic not annoying, you have anyway 3 of rubber on the bottom, I got me out of this self-adhesive protective film from the battery even additionally cut small pieces and glued on the shag, works great.
Sitting he does to 0.5mm not perfect but that bothers to 0%, as on the back.
UPDATE March 23, 2013
Battery still has 4910 mAH capacity
Indoors belongings in a Macbook 1.1 SSD and HDD rather than the CD drive and come to 4.5 hours of battery life.
