When it's being looked through, the NECG peep is no different than any other peep.
No peep sight will work great in extremely low light as well as a low-powered scope, and I've tried many sizes including "no aperture insert" for a ghost ring effect.
The best you can do on a peep would be to either go with the aperture insert removed - a "no can do" on the NECG sight, since it's used to lock the elevation adjustment - or drill out the aperture (from the front) with the largest drill bit it will take.
While most of the available fiber-optic beads work very well in bright and overcast daylight, if you used too large a F-O bead, it will work against you in dim light (like in dark swamps, and at dawn/dusk) - where a smaller/finer F-O bead will serve you better.