Definitely issues up to I believe 2015. Here's a link on the left cylinder head failure and extended warranty https://www.motortrend.com/news/chrysler-extends-pentastar-v-6-warranties/

I've never heard of it on the 3.5's and I can tell you they have been absolute workhorses in our fleet Chargers! Other than the standard wear items, the 3.5's keep on going and going and going. Less power and refinement of course than the 3.6, but we have some 3.6's with very loud lifters. Granted, they haven't been treated the best and I'm not even certain they have been getting the right viscosity oil, but that goes for both our 3.5's and 3.6's.

Our NAG1's have been durable.