All mobile data based routers such as these hybrid packages will be inherently limited by the mobile data service that they are backed by, the router itself wont necessarily have a 'better' connection to the 4G network any more than your phone does, the point is that the backup mobile data part backs the router and allows your devices to have one central point to connect to all via WIFI.
From what I understand, I think, Halo3 you have a separate mini hub, so if your traditional home internet goes down you can then change to the mini hub wifi network, Halo3+ gives you the convenience or a seamless switch over, IE the mobile data service becomes an addon to the your 'normal' router so when the internet goes down you dont need to change to a new WIFI network, just your internet has a different backhaul.
Both mobile data services probably wont out perform your phone so I wouldnt spend the money just for that, its a convenience thing if you ask me.
As far as performance inside the house, do you have a normal internet line as well with a Smart Hub or something?
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BT900 | Nokia ONT | Ubiquiti ER-X | EETV Box Pro (IP Mode) | Unifi CK2 | 6x Unifi U6+ | 2x Unifi SAK Ultra
