I went for the koutech card because it used a silicon image chip. It really isn't a koutech card at all it is a silicon image raid card, koutech is probably just the oem that put the chip on a pci card
The silicon image sata raid cards I've used on motherboards have been so good to me I decided to go for silicon image for an ata raid card as well.
The big names in raid cards are 3ware, adaptec, highpoint, and promise. Silicon image is just a little guy now but it is growing very fast and all of their products have had very good performance.
If you want to get a card from one of the big boys in raid controllers 3ware is the absolute top of the line. Under that I would probably go for an adaptec card due to all the very reliable and fast scsi cards I've used from them. I think a Raid 0,1 ata card will run you about $50 or so from adaptec.
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