This is a somewhat complicated question so bear with me...

I'm using a Powermac G5 with an RME Fireface 800 sound interface. I'm looking to add one or two external Firewire / Firewire 800 drives to store my sample libaries on (BFD, VSL Solo Strings, etc.). The Powermac has one Firewire 800 bus so I can either daisy chain the drive(s) to the Fireface 800, or I can use the Firewire 400 port for the drive(s), which will have the unintended consequence of forcing the Fireface audio interface to run at Firewire 400 speeds. (This is a known Powermac issue...but not really a problem since I've used the Fireface often on a 400 port without problems...)

Okay, so my central question is from a performance issue, in the above situation, would it be better to have 2 250 GB external hard drives or 1 500 GB hard drive for streaming samples from? In other words, would performance be more improved by having two drives "seeking" independantly, but sharing either the same Firewire 400 bus or sharing the Firewire 800 bus with the RME sound card, or, conversely, by having one larger drive which would take up less of my Firewire bandwidth while having to work twice as hard to stream samples?

thanks...