If you've played Lemmings from the old PC version, you're going to love Lemmings on the PSP!
Sound: Lemmings has a classic soundtrack - with old, retro music to accompany the retro gameplay. The sound effects of the Lemmings themselves as well is great too... the little squeals and screams as they're dying! Can't believe I've just said that...
Value: You can find Lemmings for about £15-£20, which I personally think is great value - not just for Lemmings, but for any PSP game. If you can find it for about this price, then go ahead - buy it, you'll love it! But if it's any higher, you'll complete the game and wish you got more for your money.
Tilt: I'm not really a Lemmings fun, but I've really enjoyed playing the game on my PSP. For long journeys, or just if you're bored - the little guys with the green hair can really cheer you up.