Hi Jabbran,

Ten minutes is very decent for a Cat, which is lightweight (at least when on the plane).

I've been unning fast electrics for some years now, on NiMH, the average runtime was between 4 and 7 minutes, depending on the boatsize, number of cells, motor, set-up etc.
The races I run my boats in, typically are 6-7 minutes, depending on the class, so runtime is not a great issue for me, as long as I make the requirede runtime, I'm fine. With three heats per class on a race day, I have time to recharge my batteries before the next run.
Next to that; it's hard to keep focused for 6 minutes when you're wizzing around the markers with three to five other boats...

With the rise of brushless motors and Lipo's, the more efficient brushless motors made it possible to run longer on the same battery capacity, as Lipo's are getting more and more affordable, the higher capacity allows even for even longer runtimes.

The slower the boat, running Lipo's, the longer the runtime; you can run a small tug at scale speed for an entire day on a 5000 - 6000mAh battery, but as soon as you make it work hard, by towing things, the runtime can easily be cut in half (which would still be half a day...)
Going faster, means a higher amp drain on the battery; you can't expect a speedboat to run for more than 8-12 minutes on the same capacity going 50 mph+.

More speed means shorter runtimes.
And: speed costs.

Regards, Jan.