Too good signal or just WISP low bandwith ?!?

Hi there guys,
So here is the problem, i want to get wireless link from my friend who is WISP owner, but because i dont see his AP, i needed to make a WiFi hop in order to get signal to my house. So, it looks something like this:

My House (SXT) >> WiFi Hop(SXT +PowerBeam m5400) >> WISP AP (Nano Station)

My house has one SXT5 in client mode, wich is connected to WiFi Hop that consist from one Mikrotik SXT and one UBNT Power Beam m5 400, SXT is in bridge mode, looking at my house,and the m5400 is looking at my friends WISP AP.
So, the signal that i get from my house to wifi hop is -39 / - 40, sometimes it shows me 54/54 mbps, and sometimes 54/6 mbps, any idea why?. And the signal from m5400 to WISP is -60. So, all signals are great, as i can see.

But when i try to test bandwith, i cant get more that 5/5 mbps, or even lower that 1 mbps. So i am not sure, is it me or is it that my friend doesnt have enought bandwith, wich i doubt honestly.

At that building that i use for WiFi Hop there are three more antennas from other WISP, but my antennas are like 2 meters away, secured tightly on metal fence, not on metal bar.

So, what can be the problem? Too good signal, maybe becazse antenas are mounted on metal fence, to on metal bars? In front of all antennas there is optical visibility without any obstacles.
thank you in advance.