Re: The problem with es-16-xg is not just the SFP+ cables
Sorry for your trouble here. Your findings fit with ours.
We test, and FiberStore tests, compatibility with these SFP and SFP+ modules between Ubiquiti gear to other Ubiquiti gear. We actually emailed FiberStore about this article - and they confirmed our test findings too - that the SFP/SFP+ modules do work w/ our gear (when used with our gear).
So it sounds here it's DAC SFPs connecting between Ubiquiti gear and non-Ubiquiti gear. For best compatibility across vendors, it's advisable to use non-DAC SFP modules.
We actually sell some as well:
https://dl.ubnt.com/datasheets/fiber/U_Fiber_Modules_FiberCable_DS.pdf
The 10G SFP+ MM modules are $38 for a 2-pack (so $19 each):
https://www.streakwave.com/itemdesc.asp?ic=UF-MM-10G&eq=&Tp=&o1=0
So this solution is actually cheaper than what you are using as well - as you can get a fiber patch cable from fiber store (below) for $2.60.
http://www.fs.com/products/12018.html
So not only is this solution more compatible, it's also only $40.60 for a link (not including shipping).
Cheers,
Brandon
Hope this helps.