I have used after market batteries, though not on my D7000. My experience was not encouraging, one failed so early it might have been DOA. The replacement is still around and still appearing to work but it never gives the correct response to charging. On balance I would urge the use of makers devices rather than a 'Joe Soap' special.
Nikonians®, NikoScope® and NikoniansAcademy™ are trademarks owned by Nikonians.org.
Nikon®, Nikonos® and Nikkor® are registered trademarks of Nikon Corporation.