Sneak mode has its own issues. Unless you're a superlative player, playing as Snake is a lot less enjoyable than you think it might be. Go after dog-tags and you'll regularly find yourself getting slaughtered by the two rival teams. Sneak around in the quiet places of the map, meanwhile, and you'll have a longer game, but also a fairly dull one. Arguably the guy playing Metal Gear Mk.II has a better time - at least they can run up to enemies and zap them with a stun gun, then race off at speed while the irritated foe tries unsuccessfully to draw a bead on them.
Still, when it all does come together, it's great - when team play on a Base map reaps rewards, or when a Team Sneak mission gives you a series of rewarding stealth kills in a row. The one thing to watch out for is that MGO is not the easiest game to get into. Konami has cleverly divided the available games into lobbies, with specific lobbies aimed at beginners and the average level of the players on each server clearly marked. You even get a warning when you attempt to join a server where the players are generally more experienced than you. All the same, it's a game that's heavily weighted towards those with more experience and more skill, and you can easily spend a dispiriting hour or two getting wiped out so much that you end up with no score at the end of the game - and hence no chance of levelling up and boosting your stats.
That's going to be tough on new players, but the thing that really puts me off MGO more than anything else is the overall quality - or lack of - of the overall player experience. First, having a PSN account is not enough; you have to register both for Konami's overall gaming service and the MGO program itself. Then you may have to wait longer for a patch to download, and even then you may suffer from various log-on or server issues. I'd originally planned to look at the first expansion pack, Gene Expansion, as part of this review, but every time I've tried to download the thing from the built-in Metal Gear Shop I've found it closed for maintenance. And those of you who share a PS3 won't be happy to find out that you're limited to one character per console, not per PSN account. If you want a second character or someone else in the house wants their own, then you'll have to pony up for an additional character slot or an expansion pack that comes with one.
MGO undoubtedly has potential. It's a solid online action game, the Team Sneak and Sneak modes have a lot of promise, and the more Konami can tap the love people feel for the series, by adding familiar characters or environments through downloadable expansions, the stronger it will be. All the same, it's hard not to feel a slight sense of disappointment. MGO is good, but anyone expecting an online experience as superb as that of Halo 3 or CoD4 - or Splinter Cell: Double Agent if you want another point of comparison - won't find it here quite yet. That verdict might not stand forever, but for now while this is a fine way to squeeze more value out of MGS4 if you have it, it's not a reason to buy it if you haven't done so already.
MGO is at its strongest when it embraces the sneak-em-up action of the series, and at its weakest when its controls jar with the more conventional gunplay of the Deathmatch and Base capture modes. Good, but not exceptional enough to drag players from CoD4.