ANONYMOUS LensFix and LensDoc take different approaches for fixing distortion. With LensFix, there is some front-end manual effort but when you get the settings dialed in, you are set to go in repeating the actions. LensFix also includes an ever expanding of pre-sets and allows you to correct for wavy line distortion, chromatic aberrations, vignetting, etc. while LensDoc only allows for correction of barrel / pincushion distortion. Add to that, you also get image type remapping, etc. with the other four plug-ins included with LensFix.
(Version 2.0.12)