SUPERIOR DRYWALL & PAINT SVC

I used Superior Drywall because of a recommendation from our general contractor (red flag, shouldn't have done that). His price was very competitive for the drywall and very over priced for the painting. I used their services only for drywall. 
When the job was finished I got billed extra. We had a long argument regarding the definition of "turn-key" and "quote". I was also billed extra for having to carry boards upstairs due to the weather. I ended up only having to pay for the extra boards that he under-estimated for the project, but be aware that when he gives you a quote it is only a guess as to what it will take; so if they need extra boards because his guess is wrong, you will pay for them.
I was also told by my general contractor that at 1 year they would come out and fix screw pops, corner pulls and any other issues due to settling as part of the project. I contacted them by e-mail this week and have gotten no response. 
As to the quality of the work. It is average - we have several screw pops throughout the house (but I figured that would happen). The kitchen had 6 in the ceiling that our finisher had to fix, two corners have peeled at the tape as well.