IMO, most folks here use i5/i7 processors -- just wanted to throw that out there in case you were wondering why nobody's left any definite performance feedback so far.
Most Xeons don't seem to support Intel's QuickSync feature, which BI can use for H.264 hardware acceleration (which reduces the load on the processor).
If I were you, I'd give the
Blue Iris 14-day free demo a whirl and see how it goes. Keep in mind that the "Direct to disc" feature doesn't always work during the demo period, which can cause the CPU usage to be higher in the demo than what it is in the paid version.
Also, you might consider dropping your frame rates down. Going from 30 FPS to 15 FPS will cut the processing load on BI in half, and double the amount of recordings you can fit on your disk. That thought usually seems crazy to folks first setting up their their systems (or at least it did to me), but for most folks, getting 15 pictures of something every second is almost always more than enough when you need to review a recording.