I'd know the quality of the steel in the OnGuard is high, so that almost recommends itself. The Motrax looks like its probably from the same maker as my old SuperDeals U-Lock, and since it is made for motorcycle security, I'd say its definitely not bad. The gaps in the OnGuard is very wide, so invites prise-attacks, so make sure you lock pedal-crank, downtube and front wheel all together, and to a solid post. Or at least fill the gaps as much as possible to ensure less opportunities for bottle-jacking.
I'd know the quality of the steel in the OnGuard is high, so that almost recommends itself. The Motrax looks like its probably from the same maker as my old SuperDeals U-Lock, and since it is made for motorcycle security, I'd say its definitely not bad. The gaps in the OnGuard is very wide, so invites prise-attacks, so make sure you lock pedal-crank, downtube and front wheel all together, and to a solid post. Or at least fill the gaps as much as possible to ensure less opportunities for bottle-jacking.