Okay all; i posted on this once before - some success at getting Nstreme to work stable over N links - now i've hit the mother load and im 100% confident of my results.
One caveat before we start - you MUST have an exceptionally good wireless link. That is to say your signal must be acceptable for the distance and if you are already running NV2 - you should be sitting in the 100% range on your CCQ's. Much less than this and you will actually go backwards with what i'm suggesting. So if you have a questionable wireless link, DONT DO THIS!
Right - its simple. You can have your choice of 20mhz, 40mhz above or below; single chain, two chains. You MUST be running at least RouterOS 6.7 (this is my test bed), the latest routerboot and have Mikrotik N cards. I can't speak for results on any other card - this is a Mikrotik forum and we are a Mikrotik house
Most settings should remain bog standard; except:
HT AMSDU Limit = 3839
HT AMSDU Threshold = 3839
Nstreme Enabled
Enable Polling
Framer Policy = Best Fit
Framer Limit = 4000
So long as you understand Mikrotiks other wireless settings you should have no trouble replicating my results. I have two links (both under 10km) running this set up at the moment absolutely perfectly - and i even get better results out of the links than i had on NV2. I am yet to try it on longer links, but thats coming and no i haven't tweaked the settings much more than you see above to try and get better performance....its on the list of things to do.
So for all of you out there running NV2 networks; give this a try on atleast one nearby link - you wont be disappointed!
Good luck