You can now retrofit your CFL PLL lamps with LED! Keystone's 17W LED PLL lamps bypass the ballast and wire direct.
Green Creative's PL Edge lineup includes ballast-compatible, DIRect LED PLL lamps that work on the existing ballast. 2G11 4-pin base. Their 14.5W LED PLL retrofits 36W CFL PLL lamps and the 17W LED PLL retrofits 40W CFL PLLs.