>Hello,
>
>Is the speed of SATA drives and the reliability of SATA RAID controllers at a point where they can be considered for a production environment?
>
>TIA

Yes.
Last Hitachi(IBM) SATA-II 500GB disks are with transfer 3GB/s.
Last Intel SATA-II RAID controlers support Raid levels(0,1,5,10 and 50) and SRCS16/18(6/8 HDD) www.intel.com/go/RAID/
Because for SATA is used 1HDD- 1 communication channel if you write on more than 3 SCSI disck on channel it could appears that SATA transfer is faster than SCSI one.
There is a few solutions for SAN with 12-15 SATA HDD. They could be in a cluster using FibreChanel controler or 1/10G Ethernet.

I have used that kind of SAN.

HTH