You silly hobbit.
That's not a feed - that's 15-minute-delayed-data-on-demand mechanism.
You won't get a 5 minute delayed anything (feed or data-on-demand) because then real-time royalties are payable.
Good to hear to confirm NO FREE 5-min feed at all.
Probably there is NO feed of 14-min or less.
Each country has different charging policy for feed.
I guess US has strict policy for charging, although some country provides free real-time data.