Hi, this is a re-formulated post about using a SSD for boot and apps and a HDD in the optical bay for storage of files. I still want to post it here due to the MacBook Pro specifics surrounding the drives. I am putting in a 160 for the SSD / boot, as it stands right now the drive will have not more than 60GB on it with my music, 13+ GB of mail archive and other files. The rest, movies, websites, photos and any other media will reside on the storage drive in the optical bay. Applications such as iView Media Pro and Mail Steward have safe mount / unmount behavior in terms of operations so those should be fine when the disk is unmounted. I expect to have both drives running most of the time unless is gets rough or I need juice for longer spans. What I am wondering is what strategies for keeping a smooth running combo of twin drives have people been using in terms of keeping as many files off the SDD but not corrupting the OS when reading a disk and then having it unmounted? I know the "other" thread is a good source but it is 23 pages long at this point but enough people are doing this now that it will be a common question as some point and it is really only touched upon a few times in the other thread. I have used CCC to dupe my current data in 2 locations, so I am safe to muck around with this now. I would expect it to be fine to boot off of any one of the three drives to move the 60GB working set and OS onto the SSD. Should I use one of my external backups to do the initial boot and then re-boot out of the optical to set up the clone to the SSD? It kind of makes sense to me given the fact that the HDD with the native OS will have moved from one SATA location to the other. This just seems different to me than my desktop because this is a mobile device and the way power / drives and other little details interact is worth looking into.