Hi Adam , I had one of these on my ED80 , 1st photo and it was nice after a little tweeking as already said .
It held my 1kg 31mm Celestron Axiom easily at vertical .
But if you can stretch your budget a bit go for the ' Linear Bearing ' style GSO focuser , these are stronger in all ways , this is one on my Saxon 102mm in the 2nd photo .
Both are very good but I have found the linear bearing requires less tweeking to work at it's best .
Brian.