The values repeat every 128. If bit 6,5 and 2 are not defined as above then no page is selected, the ROM page is not visible and it works just like normal RAM.
The pages don't appear in both &c000-&ffff and &4000-&ffff due to the way the data is decoded. The pages appear either at &c000-&ffff OR &4000-&7fff.
When I tested, I didn't see the pages appearing in the same location in both.
'''MK4'''