I run a data center hundreds of drives so I have some experience in this regard.
RAID5? Run away. Use RAID10 is you must use RAID at all. The ZFS version of RAID5 is fine but I suspect you don't have any Sun-based systems at home.
Keep in mind that the main purpose of using RAID (other than RAID0) is to have high availability of data. RAID is not a backup system.
I would recommend skipping RAID entirely and use Time Machine and CCC to clone your volumes every night.
Read here:
Why RAID 5 stops working in 2009 | ZDNet
http://www.miracleas.com/BAARF/RAID5_versus_RAID10.txt
Scott