Well, I've been looking at antennas and connectors for my T-Mobile gateway and most of the hype is just that when it comes to antennas. I've tried a ton of different antennas from 3dbi-8dbi and slim jim types to Alfa panels and they all do the same thing.
So, you could spend $10 for 4 antennas or $500 for some fancy looking panels that have the same cheap $10 antennas inside of them.
The distance between buildings though will make a difference in which to go with. If we're talking about a couple hundred feet on 2.4ghz it shouldn't be that big of a deal to use cheap antennas. If you want them to be outside of the glass you can get some cheap bases like
Trendnet @ $15 for dual antennas w/ a 3 foot cord. These work just as well for extending things away from the main unit or placing them on the exterior window sill.
For the antennas I've been falling back to these -
https://www.amazon.com/dp/B01N6GO584/?tag=snbforums-20 @ $6/ea on the gateway but, even these -
https://www.amazon.com/dp/B082SH6QH6/?tag=snbforums-20 and
https://www.amazon.com/dp/B097RCC4XB/?tag=snbforums-20 have worked the same. Part of my issue is I'm directly under the cell site but, if I take the GW outside and about 50 feet from the building my speeds jump from 200mbps to close to 600mbps DL.
In this situation though shooting from one building to another I would start cheap and work your way up. Even the Alfa antennas are relatively cheap at
$9/ea.
They offer "some" directionality but, I couldn't get them to do any better than any other antenna in my situation. They did improve some signal stats though but, the speeds didn't really jump like I had hoped. Through this process though I've looked at everything from panels to directional to yahi to log periodic options.
https://www.amazon.com/dp/B08M9WMDSR/?tag=snbforums-20 - $20 + cable
https://www.amazon.com/dp/B0995T2L6R/?tag=snbforums-20 - $8 -- these might do something more directional at a cheaper than $180 like your linked antennas.
https://www.amazon.com/dp/B07XSP2CFM/?tag=snbforums-20 - $54/ea - these appear to be even more directional and could be an option as well.
The triangle bullet enclosures though you see for most "directional" antennas just don't seem to make sense after trying a bunch of different options as the plastic enclosure just hides the small antenna elements inside for weather proofing. The additional plastic to me would mean less signal penetration. RF is a tricky business. Also, taking into consideration that the field of radiation gets tighter with the higher numbers and more focused w/ less room for error in pointing the signal.
