I’ve had a set of MG1s for about 18 months, haven’t serviced them at all in that time and yet haven’t had any issues with them. They are a bit soft, so do get beat up, but in my experience it’s only cosmetic – I’ve had quite a few rocky pedal strikes and haven’t managed to dislodge a pin yet.
The Nanotecs are thinner, tougher and the platform is a bit bigger, but they are heavier and (I think) marginally more expensive. Depends on what you’re looking for really.