We have two Dell Equallogic PS6000. One is our master SAN replicating to another unit in a different part of the building.
Especially the integration with Citrix XenServer (Volume creation, snapshots, Thin-Provisioning, Desaster-Recovery) caught our interest.
Those are very nice pieces of hardware. You get dual power-supplies, dual-controllers (firmware upgrades without downtime!), each controller has 4 gigabit Ethernet connections, a webbased platform-independent management, SNMP, replication, stackability (up to twelve? units, doesn't need to be the same models), SATA, SAS or SSD drives (hot-swappable), different RAID-levels (including RAID6) ...
Our service-plan is 24x7x4 and the units have a phone-home feature (which can be turned off), which alerts Dell/Equallogic in case a drive is failing.
Only drawback (apart from the price) which we encountered is snapshots not being replicated from one unit to another. Other than that, we are extremely satisfied with performance, reliability and usability.