This is the results from my tests on dslreports' mobile test...
Code:
Old Stock Rom/With applications etc.
File Size (400k) 600kbit/sec (0.626s latency) (5.702s d/l time)
File Size (400k) 522kbit/sec (0.76s latency) (6.886s d/l time)
File Size (400k) 666kbit/sec (0.615s latency) (5.334s d/l time)
Old Stock Rom/after hard reset
File Size (400k) 612kbit/sec (0.648s latency) (5.827s d/l time)
File Size (400k) 457kbit/sec (0.693s latency) (7.686s d/l time)
File Size (400k) 694kbit/sec (0.596s latency) (5.203s d/l time)
New Rom
File Size (400k) Unstable Download
File Size (1MB) 754kbit/sec (0.448s latency) (11.311s d/l time)
File Size (1MB) 749kbit/sec (0.363s latency) (11.269s d/l time)
File Size (1MB) 794kbit/sec (0.551s latency) (11.862s d/l time)
New Rom/Revision A Enabled and IOTA Reset
File Size (1MB)1104kbit/sec (2.371s latency) (8.24s d/l time)
File Size (1MB) 701kbit/sec (0.622s latency) (12.302s d/l time)
File Size (1MB) 620kbit/sec (1.880s latency) (15.075s d/l time)
New Rom/Revision A Enabled IOTA Reset then Disabled again IOTA NOT Reset
File Size (1MB) 194kbit/sec (0.579s latency) (42.74s d/l time)
File Size (1MB) 721kbit/sec (0.488s latency) (11.839s d/l time)
File Size (1MB) 675kbit/sec (0.582s latency) (12.715s d/l time)
New Rom/Revision A Enabled IOTA Reset then Disabled again WITH IOTA Reset
File Size (1MB) 813kbit/sec (0.418s latency) (10.421s d/l time)
File Size (1MB) 598kbit/sec (0.325s latency) (14.005s d/l time)
File Size (1MB) 750kbit/sec (0.446s latency) (11.367s d/l time)
Without doing a statistical analysis, I think it is safe to say that you should leave the Rev A setting in the EPST alone and not bother with it. Latency and overall download speeds increased.