I am looking at getting different filters. How many of you have used the cokin p series filter system and do you like it? Which would be best, getting a filter system like this or getting the round screw type of the filters you want? Seems to me with this system you get alot more filters for the money. What do you guys think? Also for those of you have used this. What is the make lens size can you use with the filters withit or dose it come in certin filter sizes. I know that it has the rings and you could use te stepup or step down rings with it.