Eshban -
If you look around the forum it is customery to at lease include a link to the items you wish the forum to comment on. It is a bit cheeky to expect people to do the foot work for you.
To the point - check out the following specs:
buffer size (bigger is better), burn free, R/W speeds (higher is not necessarily better but can indicate a more capable drive), media compatibility (type of disks it can burn and read), transfer speeds (higher is better), to name a few.
The drive which scores more and has more/better features will be your winner.
I would assume the newer one (830) should be an improvement on the older one (820)?