Hi Jil, bonjour (!)
I had a 8t Mac hub motor on my two former setups (58V battery): a diamond frame bike and then a recumbent. The Mac was not very reliable. The Mac clutch failed after 6000 km. I changed it myself. Mac motor is good for 35 mph but get hot after 25 miles, close to 90 C. I cannot climb high gradient (8%) without overheating the motor. It can climb a short 15% gradient but it overheated easily. i had to stop for 10 min.
Then for touring on my recumbent I switched to a MXUS 3000W direct drive with a 72V battery (20s) and I added statorade cooling fluid inside the motor . it is really another world ! 42 mph continuously without any issue with 2100 W! I barely reach 45 C after an 80 miles trip. I can climb 8% gradient at 35 mph and I have seen 65 C. I climbed last week a 20% gradient over 1 km after I done a 40 miles trip and reached 75 C. The 12F Nucular controller was maybe overheating (I put it inside a box) when I did a 20% gradient as it reached 105 C but not the hub motor. and I can use regen with a direct drive which is great to stop your bike at 40 mph and when going downhill. No more brake pads to change very 2000 km and so efficient and so safe even in rain. The only drawback is that the direct drive is much heavier than the mac motor but I don’t give a monkey since I don’t have to lift my bike.
Go for a direct drive.
Best regards,
Peterfr12