If you can find a PS3 with that low of firmware, then go for it. If you can't get one that is below 3.55 but used to be when it first came out, it would be possible to downgrade with a mod chip. There is a mod chip for the slims that is a clip on, so no need for soldering and it could downgrade to 3.55. For firmwares I recommend Rebug 3.55.2 and if you need a backup loader, get Multiman.