I'm currently using the Cokin P system which serves me well until I attach it to the 17-40mm [one of my favourite lenses] when I start to suffer from serious vignetting. Looking around Cokin offer a 'wide' angle adaptor but I'm pretty sure this only adds a couple of mm to the width before vignetting appears again. Currently I'm getting to 24[ish]mm before I lose sight of the bars, the wide would get me to 22[ish]mm. Anyone used the wide Cokin who could comment? Any other suppliers out there who offer better systems? Do Lee [£200 + VAT for 2 filters, 1 holder and 77mm adaptor ring!] offer better results at the wide end?