We owned a 2015 Heartland Landmark for 23 months before we purchased our current unit. Without a doubt the Landmark was the biggest piece of junk we have ever owned. It spent a total of two months at the dealer Heartland told us to take it to while we paid for living expenses due to being full time. The big three warranty items where having the entire roof and decking replaced due to delam (Started two months after we got it), the bed had to be removed so the bedroom flooring could be completely re-screwed because the bedroom floor was moving and squeaking when we walked on it and the large bedroom slide exterior siding had to be replaced due to delam. The issue was caused from a defective top slide seal from the factory and it allowed water to leak in before we found it was leaking. We had numerous other warranty issues that were done by the dealer, mobile RV tech and me. We had to cut our losses while we still had good equity in it. Heartland did take care of all the warranty work the issue was there was way to much of it.
Our new MS is a much better full time unit in our opinion. Just better quality materials. It is a flip of a coin on any RV now days as far as getting a good one.