Now that's a tough choice!!! I've genuinely loved characteristics of each, and each overall has been a great ownership experience.
The Avinox's integration, customisability, and power delivery are hard to beat for those characteristics. But I don't find it as natural feeling as the other two, the fixed battery and lack of REx a downside, and the rattling clutch was just downright annoying.
The Spesh had loads of torque from near no cadence, which was great for climbing tech. But the system and bike was heavy, and the chainstay too short. But the motor was very good, and the modular batteries excellent.
The Bosch is quiet, rattle-free, has modular batteries, REx availability, serviceable everywhere, and the motor itself feels smooth and natural in the way it gives the power.
The one I'm hoping is as good as it promises to be is the Maxon Airdrive S, as it seems to combine most of the great features of the others, but is smaller, lighter, and near silent driving and rattle-free. But it's also an untested entity so far.
For now, I'm well happy with the Bosch. Word has it in the next few weeks it'll be 120Nm too, which is great too.