Are DP's 2007 & back years make a better coach?

I bought a 2007 in 2008. It was a leftover model with a 2006 engine that was grandfathered. It doesn't have the EGR and catalytic converter. By from some of the post the latter engine problems are starting to rear their ugly heads. Just talk to any truck mechanic and you will get an ear full of the problems they have with the EGR valves etc. I am sure they are probably getting better these days but the first engines with the extra pollution equipment after 2006 were very troublesome.