What are the benefits of superNET wallet over NXT's?
You can send the SuperNET core coins to your GUI wallet address (MGW) and the same amount are then issued to your NXT account as crypto-2.0 'super' coins on the AE. If you wish to withdraw any back to the original crypto-1.0 coin wallet you simply send the required amount from your balance and the MGW-based multisig-secure coins are then sent to the address you specify and the same amount are deducted from your AE 'super' holdings.
Where there is a risk of losing your 1.0 wallet due to catastrophic device loss/failure without having backed up your wallet.dat, you can simply log in to your SuperNET/NXT account from any device and your coins and assets are all still there.