I've made few bones about that I like my Lennox/Armstrong straight A/C but the installation blew and swallowed.
We hired the building of our house in the summer of 1993. Ultimately should the blame for the crappy install go to the sub or the head.
My wife and I are certainly no experts when it comes to proper installs and sometimes bad things show up a few years later. I'm tempted to blame the Head Contractor, b/c there were some other...uh shortcuts.