Well Shark007 as a vested interest in people using his codec pack and branded MPC-HC
But still, after using his codec pack for year I did decide to not install it anymore and go with integrated player like MPC-HC or XBMC. Sorry Shark, but unless one has no control on how his files are created, no one needs a collection of various codecs and whatsnot on their system.
In short, a codec pack is useful for those who download episodes or movies from less than reputable site, but if you rip and encode yourself you tend to use the same few codecs that both VLC and MPC-HC decodes natively.
As for limitation in MPC-HC, I don't know what you mean by that. It does play all the files that I throw at him.