Power Saving - turnoff hard disks after an idle time

I have 1 IDE and 4 SATA disks on my server. Each SATA drive mostly serve one function. One drive for photos, another one for music etc. Though this is a file server, the disks are not used when we are away from home which is a good portion of the day. So I searched ways to reduce power and general hard disk usage. "hdparm" came to rescue in the form of -S option. Here is what man page has to say about -S option.

-S
Set the standby (spindown) timeout for the drive. This value is used by the drive to determine how long to wait (with no disk activity) before turning off the spindle motor to save power. Under such circumstances, the drive may take as long as 30 seconds to respond to a subsequent disk access, though most drives are much quicker. The encoding of the timeout value is somewhat peculiar. A value of zero means "timeouts are disabled": the device will not automatically enter standby mode. Values from 1 to 240 specify multiples of 5 seconds, yielding timeouts from 5 seconds to 20 minutes. Values from 241 to 251 specify from 1 to 11 units of 30 minutes, yielding timeouts from 30 minutes to 5.5 hours. A value of 252 signifies a timeout of 21 minutes. A value of 253 sets a vendor-defined timeout period between 8 and 12 hours, and the value 254 is reserved. 255 is interpreted as 21 minutes plus 15 seconds. Note that some older drives may have very different interpretations of these values.

So I executed the following commands.

hdparm -S60 /dev/hda
hdparm -S60 /dev/sda
hdparm -S60 /dev/sdb
hdparm -S60 /dev/sdc
hdparm -S60 /dev/sdd

And had to make few configuration changes to smartd ( to make it perform the checks less frequently )

/dev/sda -d ata -H -m root -s (S/../.././02|L/../../7/04)
/dev/sdb -d ata -H -m root -s (S/../.././02|L/../../7/04)
/dev/sdc -d ata -H -m root -s (S/../.././02|L/../../7/04)
/dev/sdd -d ata -H -m root -s (S/../.././02|L/../../7/04)

Yes there is a small delay when first navigate to any of the disks. But I'm willing to pay the penalty for the power saving and far quieter machine.