Exchanged 4082B to 4081B

Hi, I had originally bought a LG 4082B OEM for $100 Canadian.
Firmware A201

I used this drive for like 3 months, burnt abt 10-15 cheap DVD-R’s, and then suddenly the problem started

It wouldn’t read it’s own burnt Data(Software) DVD-R

Then made coasters after Nero gave the “couldn’t finalize” thing

It was very weird. Could read Windows XP CD, but couldn’t read DVD-R’s, sometime it turned into a CD drive, then nothing. I was reluctant to upgrade the firmware as it said on own risk so I gave it a try, nothing happened same thing

I re-installed XP, nothing happened. I mailed the factory outlet I bought from and they said to use Laser/DVD Cleaner

Anyways, I didn’t buy that and went to them, due to some mistake they thought the drive was bought recently and gave me a 4081B. I quietly came back

Now, this drive has A100 , works fine, but still couldn’t read the Data(software) DVD-R…probably scratched?

1)Should I upgrade the firmware
2)Does using cheap media destroy the drive
3)Do these Laser/DVD cleaner have any effect

Has anyone expericed this before…I saw few posts here or somwhere similar, and the user mentioned something abt 4082B’s having a faulty lens

Are 4081B’s better than 4082B’s?

Please share your expertise and advice