::
1.A single keepkey can store your two wallets, daily and „back up“; It is not imperative to have two keepkey.
2.You can have the same seed in other wallets, other than your keepkey (smartphone, pc, etc.). The address in each device will be synchronized with the transactions made in the same address on the other devices.
Security issues? Having two keepkeys is more likely to lose either, I suppose. And the more sites you use the same address, the more likely it will be compromised. ;-D