I'm using SME 7.5.1 on a 4 1.5 TB disks raid5 (no hotspare) with no issue at all
It's a really good news !
I've a PERC 5 controller with 4 x 250 GB (683GB).
After several years of sorting out what is needed and what is not. I've not consider replacing the discs with 4 X 1TB, fear that the system can not boot.
I still have try Out Of The Box Distribution as Zentyal or ClearOS, I've also try Ubuntu/Debian but there are too much work to configure all service that I need.
I prefer SME, that has always responded to my needs.
One year ago, I've installed an SME Beta 5 in production near a friend's (Due to many hardware incompatibility with SME 7, Dell T110), and a month later samba changed in a major way.
Given the risk of having to reconfigure a lot of workstations, the server is still in beta 5 almost a year now, with no problem.
Daily use is the best way to discover new bugs...
I could install an SME 8 beta in production at home, but I would really like to do so only when it becomes available in RC. Some contribs aren't yet ready : Asterisk, Zabbix, ...
beckynet