You might know that we've had our misgivings about Brink in the past, which is hardly surprising given how Splash Damage's unique first-person shooter is setting its sights on a lofty and ambitious goal. And as the game's release date has slipped, this is no less than our fifth look at what's on offer, which must be some sort of record. The crux of what Brink is setting out to do, is the seamless melding of single-player and multiplayer campaigns, which sets a series of objectives for two teams to battle it out over.

In a nutshell, one team defends their assigned objects, while the other is on the offensive, trying to destroy, seize or kill whatever happens to be highlighted in yellow on their HUD. That's an over-simplification perhaps, but that's about the long and short of it, which isn't a bad thing by any means. There's a narrative thread running through all of this too, so you're not just aimlessly completing missions just for the sheer hell of it, not that there's anything wrong with that either.

Choosing either the Security or Resistance team, your overarching mission is to save or destroy The Ark, the once glorious floating city that serves as Brink's eclectic playground made up of pristine complexes, rusty scrapyards and container-strewn docklands among others, with a vertiginous Security tower slap bang in the middle of it all, keeping a watchful eye on the chaos reigning down below. Now, here's more of the stuff you probably already know, just as a quick refresher: the Resistance is the ragtag team decked out in tyre-tread shoulder pads, torn clothes and hockey masks whereas Security gets the kevlar vests, combat apparel, gas masks and riot helmets.

Each team has their Soldier, Engineer, Operative and Medic classes to choose from, and you can customise your own bespoke character until the cows come home. We've gone over this before, but the sheer wealth of customisation options on offer is dizzying, from the hairstyles, colours, masks and other clobber, to the numerous rifles, pistols, shotguns and grenade launchers with interchangeable muzzles, magazines, stocks and scopes. There's all this and ability-enhancing perks to unlock, granting unique advantages on the battlefield. The level 20 cap imposed on these upgrades seems sensible too, as matches could become severely unbalanced without it.

Despite the level 20 cap, the sky is still very much the limit, and as you'd expect, we spend ages tinkering with our character to get the perfect look, which happens to be a dreadlocked psychopath in a bloodstained wife-beater with a red hockey mask. Obviously. 'Psychopath' is actually one of Brink's many archetypes that act as templates for your character, but there are many others to choose from, whether you want to mould a smooth operator or weathered badass. And you can create and store up to sixteen characters if you like variety.

Here's something else you already know too. Assigned to the left bumper is the SMART button that enables you to climb up to otherwise inaccessible areas, slide under low objects or vault over walls. It's a welcome change of pace from the context-sensitive 'jump here' bits or floaty jump button you might find in other FPS titles and allows for satisfyingly fluid movement around Brink's environments. If we had one small gripe, it's that there's an ever-so-slight delay between holding the SMART button and actually climbing, but that's presumably so you don't end up scaling a crate when you're simply trying to run.

So, armed with a souped-up assault rifle with a fat silencer, duct-taped magazine and big old ACOG sight, we wade into the first match ready for some action. Our first round kicks off with our five-man Security team – with one AI helping out against an entirely AI opposition – activating and escorting a slow-moving maintenance bot on caterpillar tracks from one side of the map to the other. Protecting the bot and staying close earns XP towards unlocking new abilities, as does blowing the gate separating our team from the Resistance. There's different jobs for each class, so repairing the maintenance bot when the Resistance riddle it with bullets falls to the Engineer, whereas reviving fallen teammates is down to the Medic, who can buff player health, boost his own and dispense syringes that can be self-administered by pushing in the left stick.

Of Brink's four classes, the Operative seems like the runt of the litter at present, with the ability to don disguises a fairly useless one next to the Medic's health boosting, the Soldier's fighting prowess and the Engineer's repair skills. Each class has its own perks that become apparent with extended play, but during our two hours or so of intensively playing the game, we found the other three classes a far more inviting choice. However, you can change classes and indeed your weapons loadout at any command post you capture, meaning that there can be oodles of variety within each match if that's what you want.

Anyway, having bested the AI, hacking a crane along the way to create a makeshift bridge and escorted the maintenance bot to safety after a stop-start slog against the clock, Splash Damage Game Director, Paul Wedgwood moves the session along to something a bit more taxing. An altogether different escort mission involving a soft human target rather than a mechanical one. We're playing as the Resistance this time around, and we're breaking out an influential Resistance figure called Nechayev with a pass code. This stuff is the Operative's forte, as there's also a safe to hack later, which has another pass code key that we need to get to a door in order to let Nechayev pass into the safe area. Trouble is, Nechayev is injured and limping along at a snail's pace, which makes the objective virtually impossible once we reach a dangerous choke point where the rival team can gather.

Wedgwood reminds us that a full team of human players will come up against some exceedingly tough AI, so it pays to band together as a team of mixed class players. Sadly, our team can't get the balance quite right, Nechayev finds himself floored and waiting for medical aid, while the clock runs down and the mission is a failure. Truly, the AI does behave like a smart human player, which is no small feat. In fact, some of the attending journos (not us) were under the impression that they were playing human players rather than AI.

Although we've been somewhat unsure of Brink's prospects in the past, we can safely say that we're now more optimistic having had the chance to play the game again a couple of times. Brink's customisation and overall look is immensely appealing, while the fundamentals of the gameplay feel tight, chunky and robust. As Brink edges ever-closer to the end of its development cycle, things look rather promising and most importantly, it has an edge over its FPS competitors, in that there's not really anything on the market much like it. Whether that will be enough of a USP for Brink is the big question hanging over it, but at the moment, we're liking what we see.

Brink is scheduled for release on May 17th in North America and May 20th in Europe.