Good Guys did a sunroom for us about six years ago. Looks nice but it's hard to get their attention and almost impossible once their bill is paid. Roof leaked and was leaking into the house roof. They return a small fraction of their phone messages but after several months, they finally did fix it. Worse, years after the build, the city came after me saying the building permit had never been completed and the inspection not done. This was a surprise as getting and satisfying the permit was the builder's responsibility. Still not done and Good Guys is in no hurry.
Update Oct 2018: After years of wrangling with Good Guys, I gave up on them. Their attitude (City is picking on us) and unresponsiveness made it impossible to get the permit (which Good Guys was supposed to do in 2009 before starting the work). Instead, I worked directly with an independent engineer. He satisfied the City's concerns easily with a few hours' work. Unfortunately, there are several structural problems that will need to be fixed. But at least I have the permit now.
Update 2 - Oct 2018: Have contracted with another builder for $8K to fix all the problems so the sunroom can pass City inspection. Telepost supports were installed but most weren't screwed down. So most of the deck structure was unsupported and way off level. Of course the deck boards had to be torn off to get at the teleposts. Also missing king post and leak issues.