you might be better off looking for line by diameter...... the thing is lots of lines that are stated to break at 15lb, but some can be as thin as 0.30mm dia.
Personally i take more notice of the diameter rather than the rated strength, and have found that 0.35mm gives me the best distance and control without risking a big birdy every time i cast. You can go a little thinner but i wouldnt go any thinner than 0.30mm, as the line level on the spool wont drop quickly enough to give you the natural breaking during a cast, and relying on the mags will cut distance too much.
In my experience anyway that is.
I now use 15lb red ice (0.35mm) on my reel, and had never had any trouble with it.