Hey mate
Furthest I've travelled that I clocked was 46km using a 16" cast wheel and 48v12Ah battery. Wheel set at max values. I haven't really gone a full length discharge since then. I'll get some numbers happening when I get my bike back on the road now its all metered.
With the MagicPie wheel, you can buy a USB cable to program its parameters. So you can set this to values that suit your speed/range/power requirements.
You can do the same with the mini motor or any others using the external Cruise Controller - having said that, I guess Andrew and myself were pointing toward a MagicPie as yes you can still change the settings, but has a much higher room for power should you want it.
You never know, having your ebike you might consider towing your shopping home, or a couple of slabs of VB at least
About the power, I have a folding ebike that has a 180W rated wheel (it peaks at 220W lol) and it goes 23km/h its 24V and has sealed batteries. So with bigger wheels yes 25km/h is possible with around 200W but it takes a long time to get there and you feel yourself shaking the handlebars trying to go faster haha
If you just want 25km/h on a flat, the mini motors will be fine. I mentioned them as they freewheel and you said you would be pedalling. Just say your batteries went flat, it's much easier to pedal a mini motor home than a Magic Pie hub. Pedaling a direct drive hub motor is not fun at all, even less fun with 2 of them...
There are pros and cons with them both, it's really your decision. Both of them can be set to cope with legal speed but have their ups and downs. Here, I'll list a couple then it's really up to you as you will be riding the thing
Even if everyone pointed toward one product it still might not be best suited for you
MagicPie: UpsPowerful, chomps hills with little to no assist
Internal controller option = simple wiring and neater
Easy to install, choosing a front motor will be a easy solution
Wiring from axle comes from the middle, not the end of the axle
MagicPie: DownsHeavy, not fun to pedal
Higher stress to wheel rim due to weight
Stands out...
MiniMotor: UpsDiscrete
Geared for torque, with freewheel mechanism so there will be no resistance when you pedal or go downhill
Very lightweight
MiniMotor: DownsTrying to take off too quick unassisted you will chew the internal gears
Any hill around or over 15-20% gradient will most likely need pedal assist
Cable protrudes out of the side of the axle, can be susceptible to damage if knocked.
Needs external controller = more wires around your bike to maintain.
Anyways good luck with your decision mate.
Cheers