Hi unseengundam,
I can tell you want I used my RAID for, but there are much wiser people on this forum that may correct me on a couple points.
First of all, I would recommend mdadm over fakeraid, since fakeraid will lock you to the chipset you were using. So if your motherboard needs to be replaced, you will most likely have to replace it with the same one.
mdadm on the other hand can be put on any motherboard, and then exchanged. I actually just did that when I went to replace an ASUS board with a Supermicro one (finally had the money to put something proper in place).
I am not sure why you would need RAID 10 over RAID 5, since all it would improve is the write speeds, but you lose 1/2 space of all drives, while in RAID 5 you only lose 1 drive's space.
So if you are after performance+reliability, then RAID 10. If you are after space+reliability, then RAID 5 (or 6).
http://en.wikipedia.org/wiki/RAID
I have a 10TB (8x 2TB HDD - 7 Active & 1 Hot Spare) RAID 6 setup. RAID 6 can survive 2 disk failures vs. the 1 disk failure of RAID 5.
I also have a 4TB RAID 5, and a 2TB RAID 5, all working just fine.
A complete resync will take around 300 minutes (if you add a new drive) if you adjust the default parameters. With default it will take 5x as long.
http://www.cyberciti.biz/tips/linux-...ild-speed.html
And yes, the array is accessible during rebuild/recover/add, but it will be slower. The only times it will not be accessible if the array cannot be started (too many drives failed/disconnected).
I would look up some test results as to what to make your stripe size and chunk size (filesystem). These can make the biggest difference in performance from what I could see.
I have 4K stripes and 4K chunks, get almost 1GB read and ~600MB write speeds on my array. I am sure that could be tweaked further, but I didn't have the time.
Hope that helped.