I have a pair of Inov8 Roclite 286GTX which have proved fantastic for me - very lightweight, very flexible, (I like to feel the terrain beneath my feet) soles very good non-slip, GTX not as waterproof as leather +GTX. Looking tatty now but have been on some rough trails - Tatra mountains, Dartmoor, Pembrokeshire & SW coastpaths, volcanic El Hierro -
However, this model seems to have been discontinued to be replaced by 320GTX or 325GTX. Slightly heavier though still half the weight of my 'proper' leather boots.