Guys do some homework, I love Hax but its not the only site out there. About the installing over DEX question I found over at another scene site this quote
Quote Originally Posted by PatrickBatman
Hey cyber, I think I already know the answer but another site's member asked me if you could install this from DEX without going to CEX, I'm guessing no, but since this CFW seems to be both wasn't positively sure. If no, then do same regular DEX to CEX procedure I take it.
Quote Originally Posted by Cyberskunk
You are correct on both assumptions..
NO it can not be installed on a DEX PS3 (converted or original).. the flag in the PUP and also the UPL will not allow it.
However convert the PS3 to CEX and you can install it and use it normally with full function.
A little seeking goes a long way, stop being lazy and asking to be spoon fed everything.
Edit: The same post also confirms that the 999 downgrader will work on Rogero's 4.21 and Rogero & E3's 4.3 CFW's.