Agreed. I tend to stick with OEM usually and will buy a Nikon battery despite my suspicion that Nikon and Canon overprice accessories like these. The charger, on the other hand, I have no qualms about a 3rd party unit. My Nikon charger is very finicky and won't charge at times. IMHO, the design is rather poor.
I have never had a problem with a Nikon charger not charging, since going to Nikon starting with the D70.