It will only do 45kph (28mph) two hours at that speed is not far. It takes them to school and back which is about 45 to 50 minutes each way. That's plenty.
I too rarely do more than an hour or two, but on occasion, maybe 3 or 4 times a year i will go outside that self imposed limit
That's not good enough even if I use surface streets. Most of the ones I use are 35-40 mph.