As I tend to lag a little behind the state of the art, especially in hardware, I may be a little out of date. What constitutes a "large storage subsystem" these days? Does that mean a 1 TB single drive, or something bigger, maybe with RAID?
The biggest single device I have (at home) is a 1 TB SATA drive which I partitioned into two big partitions and a third very small partition, all formatted with ext2. Not withstanding that I probably should have used something with journaling, is there something lacking in ext2 that would be provided by btrfs (when stable)?