My observation is relative, and no real measurement was made with proper tools, but:
On a perfectly working wireless network, with frequencies 5745, 5765, 5785 and 5805 MHz, when switching to nstreme v13, most links experience very bad performance.
When spacing the frequencies more than 20MHz apart (moving links to 5.3GH band) this are back to normal.
Could it be that nstreme revision 13 somehow programs the chipset to utilize wider frequence band??
(All interfaces are MikroTik brand 5211).
Daniel