I first suggest you choosing drives that are “hot swappable” so you can always do your operations with the system online; then RAID 5 is a really good choice (the best to my point of view).
For the array controller failure oh well that’s something that can happen but at that point the disks should still be safe enough so changing the controller should simply solve the issue.
I’ve never had any problems with RAID 5, but I think you should use more drives than 3. RAID 10 is also a good choice. I wouldn’t worry too much about the RAID controller failing, it would be more likely if two hard drives failed one after the other (it happens…).
If the RAID controller fails it doesn’t matter what RAID level you are using. You’ll still be offline until the RAID controller is replaced.