Didnt understand the point about guide suggests boot9strap over sighax,and does b9 installs on FIRM and a9 is on sd cardThat's exactly what it sounds like, and it's for both. Anytime you mess with the NAND you risk a brick; that's just the nature of these types of hacks. Another reason the guide suggests Boot9Strap over Sighax, with the verification checks before it installs.