I am planning to change my lee GND filters not sure if I want to go for the Cokin Z pro or the more expensive singh-ray filters but I would like some advise on what strength to buy and combination of hard and soft filters to buy. I am currently on a tight budget and don't want to spend too much money especially when I am not making money out of this hobby. Form my experience I find that the one stop filter I hardly use so why pay 100 or so dollars for it....