Metal Gear Solid Portable Ops + review at IGN.

"Kojima Productions and Konami released an instant action classic with Portable Ops, a title that truly brought the Metal Gear Solid universe to the PSP. Capitalizing on the technical strengths of the system, Portable Ops used Wi-Fi, periperhals and control scheme of the PSP to present a compelling story with incredible gameplay. Almost a year later, this title has been expanded upon with the recent release of Metal Gear Solid: Portable Ops Plus. While not a true sequel, this expansion pack of the award winning title is designed to add more to the overall gameplay experience. Unfortunately, the improvements don't outweigh the features that have been stripped away from this franchise, making this release seem unnecessary."

Full Source: IGN