Some of the best casting line i have come across is penn supersurf in 0.33mm 15lb , bright red in colour, smooth with accurate diameter and it was very strong it outshone everything in the 15lb dept. So of course they stopped selling it
Price was around £7-8 a spool for 1200yds on a wide drum.
You can still get this line now from usa, it is a bass spinning line and now sold from a company called izorline usa, the line is now called superline supersurf. it is available in all sizes and you can buy 3 spoolsfor 23 quid inc postage
Best i have found and i am sticking to it