Ditto the HD manual. Over the years, I've found both Clymer and Haynes to be somewhat lacking. Also, the factory manual can be resold later. A buddy was tossing out his old Ford F350 factory service manuals. I asked if I could have 'em. Sold 'em on eBay for about $90.
On the other hand, I have also found errors in factory manuals.
If you can I would suggest getting both, if you are a more experienced wrench and know the technical terms used on bikes and engines the HD manual is fine on its own, even for me, I'm from the UK and have to translate, we don't have wrenches we have spanners, fenders are mud guards, etc and for tech stuff we use metric not imperial and even your gallons and quarts are not the same as over here, two Nations divided by a common language. LOL.