It depends on the corporate finance and PE experience you are going to get, as those two are very broad categories.
In general, if you want to get an MBA from a top 14 school with 2 years of work experience, the PE experience would be better. However, it depends on the types of work you do in the PE shop, the size of the deal, etc. If you do corporate finance, it would be harder to get in to a top 14 school based on 2 years of work experience (~1 year at the time of application), simply because the breadth and depth of work you do will be very limited, especially at an undergraduate level.