Good spotting in those photos! Yes I used self amalgmating tape, replaced the rusty screws with stainless ones and chucked silicone over the connector on the antenna.

What's really getting to me now is while the burst speed of the upgrade is awesome, the latency is terrible and goes all over the show. I'll post another topic on that anyway to see if anyone else has the same problem.

Back to your setup, I can see where you are heading with your project now. Mikrotik gives the advantage it can also play the part of the router, not just the wireless client. For speed control, I've just experimented with the default access point rate setting and it actually works very well at speed capping clients to an exact figure, any client you want faster you just add to the MAC registration table and specify a speed. Nice and simple to set up. Note it only affects the transmit rate from the access point if the client is non-Mikrotik but that might be all you need anyway. Food for thought.

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Did I see you mention somewhere you live in Queenstown?