I used The Company Corporation to register my company in Pennsylvania last year. Their price was at par with other services, but I used them because I had a good experience with them when I registered another company 15 years ago (they just started their services). I just learned how they tried to trick me into more unnecessary services.
After we received a bill from them for "Statutory Representation in PA", I found out that they registered themselves as our registered agents in PA. Since our address in PA, there was no need for them to do that. The only reason they did that to continue bill us for services. We can and will change this with PA Department of State, but now we have to pay $70 filing fee to change registered agent.

This is a clearly deceiving practice on the part of The Company Corporation -- I do not recommend using them.

Then in addition to the problem I reported above, I recently discovered another problem with their service. Please read carefully not to make the same mistake, and do not use Company Corporation for your incorporation services.

When I incorporated, I selected the Subchapter S corporation on the CC on-line questionnaire. CC on-line system led me to believe that their service would register my company as a subchapter S. It turned out that I had to pay CC extra for filing the proper form with the IRS to make my company an S corporation (critical if you want to carry profits and losses to your individual tax return). Since I did buy the extra service, CC just registered my company as default C corporation without clearly letting me know. CC does not even inform their customers that a special form must be filed with the IRS after incorporation in order to register for the subchapter S status. Why then they ask their customers to specify whether they want to register a subchapter S or C? I only found out about the improper registration when my accountant started to prepare our tax return for 2010.
Again, I do not recommend using Company Corporation services.