Had to have AG replace the windscreen on my Bora at the end of June to enable me to sell the car on, no complaints from me, (apart from £100 excess on my ins') fitted with no problems, whereas when the Bora was stolen/recovered a few years before, a 'Smile' windscreen was installed and by the passenger side A pillar the glass was quite badly distorted in one place.... within 2 weeks a tiny, tiny, tiny stone chip appeared right in the middle of the distortion and the screen cracked!
Also a screen replaced by AG is guaranteed for as long as you keep the car, dunno how good *that* is tho.... a stone chip is a stone chip and will usually get repaired for free via your ins' co' if glass is underwritten in your policy.
I have no reason to think that AG glass is in any way inferior to the original, whereas 'Smile' Windscreens I would keep away from.