PE? You need to start learning more about companies. High PEs can actually mean that a stock is set to rise because people are expecting higher earnings in the future. as for CCI, it is basically a REIT and PE is meaningless. You need to look at cash flow and debt service coverage. Eventually, CCI needs to kick out a major dividend.
It's also helpful to know something about the tax code. As long as CCI can shelter income from taxes they'll continue to be a C corp, which lets them invest the cash flow in growth and stock buybacks. When the management team no longer sees growth opportunities, CCI would convert to a REIT, like AMT did. Of course, then the team runs the risk (like Global Signal years ago) that a growth oriented C corp could buy them out.