M-Audio 1814 and Firewire solo

They do use the same drivers. I think if you want to sync them you have to use S/PDIF, though, if I remember what M-Audio tech support told me correctly. Daisy-chaining them should also be possible, although I should note that I recently eliminated a hum in my mixer by plugging in the power brick of my FW410, which I hadn't benn using with my desktop DAW. But that probably varies by hardware setup. There's certainly no harm in trying it.