Outward opening is unusual and always gives delivery drivers and ad hoc visitors a shock.
I have rarely had them fitted on properties I have owned or managed, as inward opening is much easier to set up. I used to use underground motor units as they are much more discreet and I think this is the only realistic option for outward opening.
I tend to use CAME. For both types. I have found them durable and reliable, and fairly easy to programme (don't underestimate that bit - set up of the safety and loop systems can be fiddly).
Overspec them. This is important if you want longevity - do not push the motor v maximum gate size.
Bear in mind that if you use solid gates (as opposed to say wrought iron) then in windy conditions the fail safe systems may prevent system operation especially if you have been mean with spec, as the gates work like a sail and trigger the safety mechanism.
I have wide, solid timber gates (opening is about 5.5 metres overall ) and I did not know it when I installed them, but my N/S oriented drive turned out to be a wind corridor in stormy conditions. I over-specced quite a lot but in high winds the mechanism can struggle.
Make sure that whatever system you get, the manual override is a) easy to operate and b) secure (by which I mean properly lockable).