I've used the CalDigit AV drive on a MBP or on a MacPro and it's very fast - USB on a
single HDD is
comparable with eSATA and had no issues with video editing ProRes HD or DNxHD.
Via USB3 the Caldigit AV drive does around 128MBps Read and 100MBps Write
It also has FireWire 800 but via that connection it only does around 85MBps R/W
I was cutting a mix of ProRes 422 1080p25 and XDCAM EX 1080i50 with no issues.
If you were to link a USB 3 RAID then you could expect nearer the theoretical bandwidth of 4.8GBps (realistically 3.2GBps or 400MBps) on one connection.
Whereas eSATA 3G carries only 3GBps (realistically 2.4GBps or 300MBps) per channel although 6G is available and can carry almost double that but you need to connect HDDs in a RAID or SSDs that actually provide you that bandwidth or its all overkill.
So short answers - yes and yes - CalDigit and Normal workflow for Direct Attached Media Storage.
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