Could someone explain what the difficulty setting actually does?  I'm using an Innosillicon A4+ to try and scrypt mine DGB, but have no idea what adding a difficulty number does or what number I should even try adding.  Thanks.

Received this from Baikal yesterday.

"Thank you for your contacting.  I am sorry the Giant-B is currently out of stock. Any updates on stock we will let you know by making announcement on facebook/twitter. You can also pay some attention on our website."

Yep, thank you.  So a copy of an HD wallet saved in a safety deposit box, will always have the same balance as the original, no matter how many transactions and addresses are made?  and the password isn't changed.

Thought of a new question.   Are most wallets basically the same?  If I create a wallet in Bitcoin Core, can that wallet be used in Electrum and visa versa?

Thanks for the replies.  How do you tell if it's a HD wallet?  One reason I was asking this question is I wondered if I put a copy of the wallet in a safety deposit box, if that wallet would have the newest balance on it if something happened to the original and I were to use that copy at a later date.

Say I make a few backup copies of my Bitcoin Core wallet and save those copies a few different places.  I then continue using the original wallet for a few moths adding new funds to it.  Will the backup copies I made earlier automatically have those new funds on them if I lose the original wallet or does the original wallet need backed up again every time new funds are added?  Thanks for any responses.