I am on the verge of ordering a DR1000S

. Two questions:
1. I see that there are two different covers available; a "flip" cover (which I assume opens vertically?) and a "deluxe" cover which open horizontally. Which is the better? Do both hold the machine in securely and provide good protection?
2. There is a "power supply" accessory available. Is this just a standard USB mains charger, or something fancier? If it's a standard USB charger, I shan't bother with it.
Thanks!