Just under a year ago, Niall Harbison made a fairly bold declaration on these pages: that Super Miss Sue, the then-brand new seafood restaurant on Drury Street, was the best restaurant in Dublin.

Not the best seafood restaurant, he said. Not even the best new restaurant. Just the best.

It's a massive claim, and one that's weighed heavily on many a punter's mind as they walked through the stylish black doors and into the snug, minimalistic surrounds of the D2 joint.

Expectations are funny things; double-edged swords that can either provide a naked emperor with a set of fancy threads, or destroy a well-dressed monarch for not quite reaching the lofty standards of their office.

So all these months later, with the dust settled and the novelty factor a distant memory, is Miss Sue still as Super as she used to be? Restaurants, after all, are prime candidates to become victims of their own success – overcrowding due to demand, overambition due to hype, lack of focus as the team turns their focus to sister projects, pop-ups… and popdowns.

It's the question of demand that runs across my mind as I take my seat, set up with no more than a two-inch gap from the neighbours. I smile a polite hello; a brief scan of their plates reveals that they were just tucking into their mains, so we're going to be sharing close quarters for another 45 minutes at least.

My dining partner, Sinéad, joins me a few moments later; she flashes me a glance as she surveys the layout, and I watch her brain follow the same thought process as mine had a few seconds earlier. There's casual, there's cosy and there's conversation-killing… and this was not a great start to any evening.

The menu at SMS largely provides a backbone of dependable dishes for the kitchen to operate off on a day-to-day basis, but the specials are where the real quality is to be found. Based on the best available seafood produce of the day, this is where you get some of the highest-quality fish dishes in the city.

I opt for the seabass while Sinéad orders the monkfish, both with a zesty lemon dressing – but that's still an entire course away. For now, the starters are a far more exciting prospect.

We both choose oysters, albeit presented in radically different forms; for her, a tempura served with potato foam, leek and smoked haddock oil, and for me, served with an incredible mix of vodka, cucumber vinaigrette and caviar. And you know what? It's absolutely premium, the oyster providing a sublime texture to stand out against the explosive taste of the vinaigrette and the salted glass.

This is as tasty, as complex, as ingeniously designed as food gets. I'm glowing, beaming across the small table at Sinéad who for her part is looking damn satisfied with her tempura, and our dining neighbours may as well be spaced five yards away from us at this point; these starters have catapulted our other senses into the backseat.

And so the expectations game continues to get that little bit harder for SMS, who have yet to present us with our mains. Lads. You don't make it easy for yourselves, do you?

There are few culinary challenges greater than presenting a straightforward fillet of meat or fish, with only a sliver of dressing to hide behind. Throw in the fact that the sides are presented on separate plates – we get Cervi fries, served from the adjoining posh chipper, and a cabbage and seaweed salad to share – and you're left with a laser focus on the quality of the cut.

It's a bit like playing Italy in the Six Nations; even if you win, there's a queue of people telling you that it could have been done with more style, more panache, more passion, more flair. And if you lose? Well, goodnight.

So while the seabass at SMS is a storming, six-try victory, where every pass connects, every penalty sails between the posts, and every play comes off seamlessly, it's hard to get as excited about this as one might about the intricate and intriguing starters.

Suddenly, we're back in the company of our noisy neighbours – and the wine (a delicious 2013 Cotes du Rhone, unconventionally chosen in spite of the fish main) becomes the focus of our distraction, complementing the lemon dressing in a most unexpected but enjoyable way.

The cost of the mains – €20 for the monkfish, €25 for the seabass, with the sides costing an additional €4 each – is also a looming reality at this point. Casual dining with a bill of €60, ex-wine? That's far more difficult to swallow than our oyster starter.

Sure, the vodka and cucumber viniagrette starter may be the best thing I've tasted so far in 2015, and the main constituted as good a fish dish as you're going to get on this side of the Shannon. The tunes are great, the tie-in with Cervi is ingenious and the Popdown extension is certainly one of the most excited spots in town – it's a tremendous setup, make no mistake.

But the best? The one you'd recommend to someone who was in the city for one night, and one meal?

Maybe not. Maybe there's no restaurant in Dublin that could stand up to such a lofty title, and be the go-to answer to that dilemma. But if there is, it's probably not Super Miss Sue.