I might try some internal ones to see if it improves anything. At the very least, it might let me move the 5G router to somewhere more out of the way while retaining the same signal strength.
This was installed on a warehouse refurb. They weren't keen on sticking it outside, so they have the massive aerial on the window sill. The speed was up to 7mbps download which was a 700% increase.
Coat quite a bit though!
11dbi aerial and it is about the size of half a box of A4 paper reams
I'll be doing an install of something similar tomorrow. I'll let you know how I get on. It's at a warehouse in acton.
It's a big wedge shaped directional antenna