[GA-Z68X-UD3H-B3] RAID10 on mixed SATAII/III ports

The GIGABYTE GA-Z68X-UD3H-B3 has one Intel SATAII channel dedicated to a eSATA port, leaving it with 3 x SATAII and 2 x SATAIII headers. According to the specifications, it supports RAID10 on these five ports.

Is there any problem running a four disk RAID10 on a mixture of SATAII and SATAIII ports?

I see no problem as it's working on 1 chipset and one controller. You have all drives on the same list in controller BIOS with build/rebuild options and it's working as standard RAID like it was in older chipsets ( P55, X58 ... ).