Tom's Hardware Guide has reviewed five Serial ATA II controllers today:
We received five RAID controller cards - one a x4 PCIe unit, while the others running on PCI-X - all designed for 'Serial ATA II operation'. The problem with this is understanding exactly what it means. Anything that exceeds the common SATA 1.0a standard (150 MB/s per port) is that it either isn't part of an adopted standard (SATA II does not equal SATA 2.0) or it leaves room to add features as an option (SATA 2.5). So if you insist on having certain SATA 2.5 features, such as 300 MB/s bandwidth, Native Command Queuing (NCQ), staggered drive spin-up, port hot-plugging, external SATA (eSATA) connectivity, activity LEDs, logging or port multiplying, you still have to check these one by one - SATA II will not guarantee you get them.