I am really interested in which one gives better performance so please post your results.
OK, so I ran my first set of performance tests.
Firstly, I left my ESXi NICs as "flexible", and ran some download/upload tests from 2 different SpeedTest web sites. Then, I rebooted pfSence, with the NICs set as E1000, and re-ran the same mix of tests, from the same web sites.
The numbers were almost identical, with the E1000, possibly, a tad faster, although it could have been in the realm of statistical differences. However, the RRD graphs showed something different.
The far left spike, is the "flexible" adapter. The next spike, at 12:00, is the E1000.
The block, on the right, was when I was running some "real life" scenarios, downloading a bunch of stuff via the NewsGroups.
Interestingly, once I switched to E1000, I got this from ifconfig:
media: Ethernet autoselect (1000baseTX <full-duplex>)
But, dumping the configuration XML, it still has:
My next test, when I get chance, is to switch back the "flexible", and run my NewsGroup download again, to see what rate I can achieve with that. I'll post, once I've had chance to try.