What operating systems do you plan to use?
Anything with the Silicon Image chip seems to be highly favored these days.
However, I am using the Promise SATA150TX4 without any debiliatating problems. Of course, I think a 66MHz PCI bus helps a little as well. 🙂 My current obstacle is finding a PATA-to-SATA adapter that will actually work with this controller. Koutech and HighPoint converters have failed to get my last (of 4) hard drives over to SATA. Currently running all flavors of Windows, along with Gentoo and FreeBSD.
-SUO