Any user reviews on the above filters in terms of quality produced?
Why don't you do a search yourself? There are already lots of comments on them. I did a search earlier and got my answer.
no complaints with cokin.. good luck finding them locally tho
Lee filters is another trusted range. Cant get locally though...
Canon 5D mkII|24-105 F4 IS L|70-200 F4 IS L|135 F2 L|580EX|