Not Impressed! I bought Power CMS in October 2009 and within two years it has been rendered useless. In my experience, when a software package is to be no longer supported the developers inform me well in advance and offer upgrade options. With no warning, I now have several clients who find they can no longer user their CMS! Yes, they can use an older browser etc but that is far from ideal.
Because Power CMS 2 is a single user license, to upgrade all my clients will be expensive. I chose Power CMS specifically because it was not limited to a single website.