is the lee holder easier to get in on? i find the cokin fine, but getting it on and off can be a real pain.
Like condyk says, very easy. One spring-loaded brass clip is all you need to touch...no little plastic pins to fuss with, and with the Lee holder the first filter slot is functional. Not so on the Z-Pro without first having to manipulate the three pins (at least that's my experience with the Z-Pro...to others, these issues may not matter at all). Not trying to slam the Cokin, just pointing out some differences...

