I am always using debian/Ubuntu as my LAMP server, this time we are about to setup a RAID1 LAMP server, the officially supported release includes SUSE and RH. Just want to know that do I need to use SUSE / RH instead of debian/Ubuntu?
If you use a Dell RAID interface and they only support drivers for that interface under Redhat and Suse, I would go for one of these two Linux flavors or Centos. Centos is practically spoken a copy of Redhat without the Redhat logo's and price tag and Redhat hardware drivers work unmodified under Centos.
There is IMHO no reason to go for RAID for improved data safety and at the same time choose a Linux version which is not officially supported by the RAID driver manufacturer. If the combination of Linux flavor and driver causes an error, it is easy to corrupt all data on your two disks simultaneously without a possibility to restore your data.