Well i don't know if the Astro Turf used on sport pitches are different to riding surfaces but if they are the same then i would avoid like the plague!!
We have a 2 meter wide strip that goes from the outdoor school, down between the fields as a path. It used to be a football pitch but the YO bought it from the local sports center when they were renewing their pitch.
Its very slippy when wet and even more so if you get a bit of mud on there...I've slipped over twice in the last couple of years...luckerly the horses i was leading just looked at me and nobody was around to laugh at me!!!!
It has also ripped in places and although the YO has tried to repair it, it's either become dangerous as it's like a hole in your carpet, you can get your foot under it or the patches move.
You can't chuck salt on it as it rots it very quickly so in weather like this (Snow & Ice) it's a death trap and one of the reasons allot of the horses have been in for longer over the last few days...even one woman who turns hers out in all weathers regardless has kept them in for 2 days because of the path!!