afaik there is only 1 0+1 mode ... 2 drives operate as raid 0 for performance and the other 2 mirror the first 2.
Depending how sophisticated the raid implementation is it potentially can give very fast performance for reads by picking the drive that already has the head positioned closest to the sector to be read. I expect this kind of optimization tho is only implemented on high end raid cards designed for servers. There are a lot of parameters in play that would affect how different applications/access paths perform vs caching levels, file layouts etc.
So the only way to really tell which is best is to measure or feel how it works for you in you normal usage patterns.
Raid 0 is usually gonna be best for perf but I don't think i would care much about a slight perf improvemnt that may not be noticable to me if a single drive failure requires a reinstall or causes data loss. Raid 0+1 avoids the single drive failure, but will suffer a (slight?) perf penalty on writes since 2 drives need to be written. If i did a lot of benchies i might want raid 0.
Where I use raid 0 on my new setups if for a small volume used for temp files in ripping/encoding and for the pagefiile since i don't care if i lose them.
In your case, since you have a bunch of slower 5400 drives, and drive space isn't too important, 0+1 seems like a good idea.
For me, with large 7200 sata drives, raid 5 seems optimal since it only loses 1/3 the space for redundancy vs 1/2 for raid 1 and i only need 3 drives vs 4 for raid 0+1.
Older raid implementations may not let you convert from 1 raid to another.
But if it does, it might be an interesting test if you have the time to try a single drive first, convert it to raid 0 and then convert it to raid 0+1. That would let you see what kind of performance differences you would see and whether the extra complexity of 0+1 is really worth it.
If you do some testing like that, also test out drive rebuild scenarios by unplugging a drive while running. Most ide setups won't support hot plug/unplug but it is physically safe to just power off a drive. system restart is required to plug the drive back in.
I did some of this kind of testing to get comfortable with raid when i first started using it. It is nice to have a test rig to do it on so you can do other things while reinstalling os'es and rebuilding raids. Much better to learn how to do it when you have time, rather than when a drive actually fails.
