Neither one. 24V was obsolete 20 years ago and 36V is circling the drain. I don't know anything about either of these systems but they sound like time wasters. If Leafmotor, EM3EV, GRIN, to name three have anything in your power range then do a comparison. In Europe where 250W is the legal maximum you can get quality systems at that power level. In the US where 750W is the legal maximum, 250W systems are being put out there to pick off the unwary. You need torque arms for front wheel installation. People will tell you you don't need them for <250W. I don't agree. A torque arm is cheap insurance. TL;DR: e-bike systems need to be over-everything to be practical. You need twice as much battery capacity and motor power as you are actually going to use. It is frustratingly counter-intuitive but if you buy a 250W system you will be using the motor and battery at their limit all the time. This will wear things out quite quickly.