No rss feed residue will be present. The phone will be completely clean and new. The device can be a meego, kernel power, stock and nitdroid phone with multiboot , but still emerge brand new after a full flash. But if u do this with a cssu phone. . . residude will appear, And even worse fact is that if u even reflash a flashed cssu phone the rss resudue will still be there. Thats the sacry part of this bug, some how the cssu has made its way to memory where even flashing does not format.