I have an EVGA Classified motherboard, and I use on-board RAID 1 (mirroring) with 1 TB drives. In use for the past 18 months, and I am very satisfied with it. I have never bothered with the speeds because it has not been an issue for me.
I also perform frequent backups to an external drive. Alternately used Win 7 Backup, and Easus Todo Backup. Both are great.