Should i cfw 4.30 to dex 4.25

Hello

I have two ps3s
Slim and a fat

Currently the fat is running 4.30 rogero cfw and slim is running ofw 4.30. I want to know the best option because i want to create backups of my games i have now and play them on the external hard drive.

But the fat has a broken blu drive i was thinking of converting it to dex 4.25 cause i heard you can using bdemu to play any game discless on a external hard drive with a ps3 that has a broken blu ray or can this be currently done on rogero cfw 4.30???