my only experience to date was in a small, poorly outfitted community darkroom. now that i'm building my own, i nead a good easel. i was planning on getting a two blade 11 x 14 to cover most of my work. i've never used a four-blade and can't seem to convince myself that they are better by looking at the pictures of them, but that could be because i don't know how they work. could someone who's used both types give me some opinions? thanks.