I have made a lot of money off USG, but I don't hold it past $20. My concern is that during the downturn, the number of companies manufacturing drywall has remained the same and they took on more debt. Whereas the home builders, all the small and most of the mid sized builders have left the market. Furthermore, most developers have just stopped as banks have pulled all financing.
As we move further in this recovery, we will not see the huge number of homes being built as in the past. But with fewer builders, the active builders will see more business than in the past. On the other hand we have the same number of drywall manufacturers dividing less total demand for their product. This will make it difficult for them to service their debt load and reduce their interest expense.
At some point USG will be bought out as construction suppliers will see consolidation in the future to reduce this competition. Their debt load will keep them from buying someone out.