I've enjoyed reading some responses. While I can't usually help with answers here on Moparts, M bodies are my specialty! Mark knows them too! RWG had a great answer.

They are NOT rust buckets, nor where they unreliable. Quite the contrary. The body integrity was great, and they were extremely reliable cars. '85 and up got even more galvanized steel. Of course, they had a few spots prone to go bad, but overall, great, solid cars! The last of a LONG lineage of Chrysler rear drive, solid axle, torsion bar suspension cars. Slant sixes and 318's! I have owned a total of 7 of them over the years. One civi, and six AHB's. I have just the one AHB now, my '89. I love them and would recommend them to anyone. Some of the earlier AHB's had issues with the shock tower failure under ABUSIVE DRIVING in Police use, yes. But '88/'89 got better K frames. I've never had one with that problem, but mine were all either '88 or '89.

Cops didn't love them for their speed with the 318-2, and 2.2 gears, but they loved the just right size, handling, and super tough looks. The 318-4 and 2.9 gears felt much better. I've owned several of those and punching it off the line would always break the back tires loose (I know that's not something to write home about, just giving you an idea of how they weren't sloths). I'm always tempted when a nicely preserved AHB pops up on the market!

You can still find PLENTY of Fifth Aves for sale. AHB's are much tougher to find. They haven't been built for over 30 years, and obviously rode hard!