Chest farming: any difference where?

Just wondering. Is there any difference in EotN if you farm chest hm, nm, dungeons, explorable zones? Since they all take the same lockpicks, just wondering if it's any smarter using them in certain places.

Smarter to use them in hm, the normal mode chests have terrible rewards.

I think that the possibility of perfected mods on your wepons is much greater in HM then in NM.

Apparently theire is a higher chance of getting lower req and rarer items.

I am not sure if the above are true although i find that my mods are considerably better in Hm as for the second statement, that remains to be tested

EotN chests have the worse drops you can imagine, its not worth chest running it.