We standardize on RAID 1 for OS, RAID 1 for logs, RAID 5 for data. Sometimes split that further. For one high end DSS system we went with RAID 10 for the data to speed reads, but it was $$$. Hard to justify the cost for other systems.
Steve Jones
http://qa.sqlservercentral.com/columnists/sjones
Follow me on Twitter: http://www.twitter.com/way0utwest
Forum Etiquette: How to post data/code on a forum to get the best help
My Blog: www.voiceofthedba.com