Getting through Ratchet & Clank: Size Matters will probably take the average player around seven or eight hours, but with more weapons to see, hidden titanium bolts to find, and side quests, like hoverboard races and space shooting, to master, there's more there for the completist to play with. On top of that, the game has a four-player multiplayer mode that can be played locally or over the Internet. There are a handful of different game types, including basic deathmatch and other, more objective-based modes, and the online section of the game has handy little perks like buddy lists, scoreboards, and so on. The shooting-based gameplay found in the multiplayer works just fine, but R&C has always been at its best when it mixes the shooting with the platforming, and as a pure shooter, it's a bit lackluster.
Graphically, Size Matters just about matches the PS2 games in quality, which is to stay that it looks outstanding for a PSP game. The game cuts away to prerendered scenes for story sequences, which is occasionally jarring since the Ratchet you see in cutscenes isn't wearing any armor, while the in-game Ratchet reflects your different armor choices. But the game runs smoothly, and the creatures and environments all have a lot of character. The game also maintains its superb looks while delivering pretty large areas, and the Clank space shooter levels look really cool. You'll notice the level of detail decreasing as you get farther away from something, but that doesn't take away from the game's looks.
This series has always had a pretty good sense of humor, and it gets that humor across with great voice acting. Ratchet and Clank are both expertly voiced, and all of the bit players you meet along the way are just as good. The voice(s) for Luna are especially great. But the sound effects aren't quite as outstanding. While the game uses a lot of the same effects as the other games in the series, your hits with the wrench don't really make any sort of satisfying "thump" sound, so it's sometimes hard to know if you're even hitting your target. Likewise, most enemies with up-close melee attacks don't make much noise when they hit you, meaning your draining life meter is the most obvious indicator that you're getting hit.
Overall, though, Ratchet & Clank: Size Matters is a great PSP game that faithfully duplicates the Ratchet & Clank experience in a handheld format. Anyone on the hunt for a rock-solid action game will find plenty to like in Size Matters.