Where to put logs in a RAUD 1+0 system

I'm about to configure a brand new, fast RAID 1+0-based system which will use logged sbspaces. Conventional (JABOD-based) wisdom tells me to put the logs on a separate device to the busy storage spaces. But, on a 5-disk array, does this idea justify holding back one disk for the logs and just configuring RAID 1+0 on the other four? Is it worth it or is the idea simply too messy? The system will be quite lightly loaded but the sbspaces could make up the bulk of the activity and could actually be written more than read. If we went for just sticking the whole lot in a single array, is there any point in putting teh logs outside rootdbs? Many thanks, Andy Kent Bristol, UK -- Shiny new genuine reply address.