i bought it... it is legit product from amazebreak.cc and it upgraded properly too. not sure which chip it has and what other kind of firmware i can install onto it, but it worked for now.
a) it works with new firmware for the chip from their website, but not with newer ps3 firmware/os revisions.
not with this chip... i saw a video of logic sunrise team booting their chip with a ps3 and os3.50 plus it is online so perhaps online features are coming again soon, but you can bet it will not stay safe for long.
c) at the moment you still need os3.41 on your ps3 to run this chip.