Here’s an honest, practical review of what you can expect from such a download: Overall Verdict: 2/5 – Proceed with extreme caution.
It sounds like you're looking for a review of a search result or a file claiming to be a portable version of Need for Speed: Underground 2 for PPSSPP (a PSP emulator), found via Google. -PORTABLE- Download Game Ppsspp Nfs Underground 2 - Google