I never could understand the mindset of backing up BluRay disks. It is really silly economics if you think about it. Just look at the cost for a 50Gb blank. Now say you have 50 titles to back up, You have to do every one of them because you'll never know which one will be so damaged it won't play. How often does that happen? Consider the numbers that it may happen 5 times at worst case odds with 50 in your library. I think it would be far cheaper to just go out and buy a replacement disk for the one to five that got lost. Plus, maybe by the time that happens that title is on sale. With the burn yourself safety backup, you'll probably be paying $200-$300 per title for insurance against losing the few you will over the lifetime of BluRay.
If you are "insuring" total catastrophe, then it makes more sense IF you store the backups off site otherwise they are likely to be destroyed at the same time as your primary disks.
Personally, I'd rather just rent the BluRay for cheap and if I really want to have it here, BlockBuster and other resources has a huge selection dedicated to previously viewed titles that sell for much less than the cost of making an illegal copy.
Yaz- unless you really enjoy spending dollars to save a few pennies, I suggest you look into the costs involved and compare to previously viewed titles prices. It makes much more cents, even dollars!