In a vacuum, the SL-K890PRO-939 would be a reasonable board. It needs a nip here and tuck there, including 0.5x CPU multiplier steps and temperature-controlled CPU and system fan headers, but it's a generally decent K8T890 implementation. Soltek even manages to mask the chipset's weak storage and networking capabilities with auxiliary chips from Promise and Realtek.
Unfortunately, the SL-K890PRO-939 doesn't have the luxury of living in a vacuum. Its world is populated with nForce4 motherboards that serve up faster chipset-level Gigabit Ethernet and more robust RAID capabilities than VIA's dated VT8237 chipset provides. This lack of feature parity with the nForce4 family, particularly the Ultra, is really the crux of the SL-K890PRO-939's problems. Were the SL-K890PRO-939 cheaper than its nForce4 Ultra-based competition, the missing features would be easier to swallow. However, the board's $122 street price puts it right between low- and high-end nForce4 Ultras. That's a tough sell at best.