I have to agree that in my experience DAS is a better solution is some cases. I recently worked on a project where the size of the databases ranged up to 1.5TB. Most of the work being done was specialized datamining processes. When we were on a 4-way 8GB box with SAN drives we were having a subset of our standard queries run in 4+ hours when we were the only user using the SAN during the test perior.

I then pushed to create 2-way 4GB test box with a lot of DAS. We went with RAID 10 storage for Tables and Indexes and RAID 1 for log files. TempDB had its own RAID 10 Volume using multiple files to avoid hotspots. The Indexes and Tables had their own filegroups comprised of multiple files. After the data was loaded onto that box and all of the Tables and Indexes put on the appropriate filegroups we reran our test. Our test ran in less than 40min.

Both environments were retested and we veriefied that indexes and the like were the same and optimized. I came to the conclusion was if the overhead of administration of the DAS boxes was worth the performance increase, then DAS was the way to go. On the other hand if ease of backups and the ablility to make quick copies of production was necessary, then SAN had a lot to offer.