Running XPEnology under ESXi is awesome. Sorry, I can't talk you out of it :)
I have a whitebox running a Supermicro X9 board with Mellanox network cards and pass through a LSI2308 SAS controller to the XPEnology VM and it works perfectly for me.
This is with SMB and 8 x 3TB drives in Raid 6...
Running a 1000MB file write on W: 5 times...
Iteration 1: 819.93 MB/sec
Iteration 2: 657.03 MB/sec
Iteration 3: 611.12 MB/sec
Iteration 4: 616.80 MB/sec
Iteration 5: 638.62 MB/sec
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Average (W): 668.70 MB/sec
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Running a 1000MB file read on W: 5 times...
Iteration 1: 1076.32 MB/sec
Iteration 2: 1391.45 MB/sec
Iteration 3: 1446.50 MB/sec
Iteration 4: 1477.59 MB/sec
Iteration 5: 1297.04 MB/sec
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Average (R): 1337.78 MB/sec
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