For me, the short answer - Nemesis any day of the week.
The long answer...
If we're taking things such as nostalgia into account, then theoretically, Smiler should easily win this battle. I first visited in the back end of 2012 and wondered what would end up in that pit, and used the build as a way into theme parks - so I owe a lot to it really. It was mysterious, tempting - what on earth could they do next? What will 14 inversions feel like? How on earth did they cram so much ride into such a small space?
Considering just the layout, it's visually one of the most compelling rides out there - having two trains weave in and out of this massive structure, in a way that's difficult to follow, yet they both somewhat mirror each other - genius. Much like Ripsaw, it's a great ride for spectators, and it almost certainly inspired what Phantasialand would do with Taron a few years later. It took me a good few years to build up the courage to actually ride the coasters, but I'd always get a kick out of the sheer scale of The Smiler.
When I did eventually ride it, I will admit that I did feel a little let down at first. The constant inverting, with nothing between to add some variation - it felt pretty predictable, and a little too nauseating, with a little rattle that at first, wasn't too bad - but this eventually developed into something that would be intolerable. A little jankiness here and there can add a lot of character - heck, this is why wooden coasters are popular - but there's a difference between out-of-control craziness and flat out pain, which is something The Smiler has often darted between. In recent years, it's definitely taken to the latter - well, even in the early days, I remember people talking about the third train in hushed tones due to it riding much, much worse than the others. And that's an issue itself - if you have to hope that you're not getting the uncomfortable train, then there's a fundamental flaw in the ride, and it becomes a lottery of hurt.
Progressing through the years, it seems that most of the trains ride like the infamous third one now. The whole thing feels like a shopping trolley with square wheels that's falling apart and being moved around too aggresively on a cobbled street. Again - rides don't have to be perfectly smooth - but I don't want to come off one with a headache and to feel a bit ill. Then there's the odd bumpy transition - the bottom of the first drop, the cobra roll - that judder the body in such an uncomfortable way that - even if you've been blessed with a relatively smooth ride up until this point - there'll always be these jolts to bring it back down a little.
If we're speaking about the wider experience as well - it has all the charm of a run-down council car park. It's dumped in a big concrete box that's soggy and rotting, and the queue is just a claustrophobic, chaotic cluster that really isn't fit for purpose. One of my least favourite memories of the park as a whole is being stuck in this slow moving queue one night - being shuffled around with no sense of progression, with highly irritating music for an hour - it really isn't great.
All of this is made the more confusing, when on the other side of the park is something as exceptional as Nemesis, which predates The Smiler by almost two decades, and does everything to such a high quality that just isn't seen in X-Sector.
Before you can even see Nemesis, there's a sense of drama in the air - slowly descending towards this huge arch with the distant rumbling of the ride, and then the path opening up to the chasm of natural rock, track and this grotesque creature - already the experience exceeds the aformentioned Gerstlauer.
Nemesis may be short, but the pacing is relentless - each being ridiculously intense, with the inversions spread out enough so you don't feel too sickly. And the way it's paced, man is it creative - starting with the corkscrew and building up to the crazy zero-g roll before the loop, and just when you think it's mellowing, another corkscrew to see you home. And because it is short, it makes it easier to lap - although I've never really been able to do more than five or six in a row before the effects of one Smiler ride set in. It did get a bit rough towards the end of it's life, but I never found it to be that bad - and to be fair, when a ride has been running for almost three decades, it's to be expected.
The setting of the ride as well - such a unique setup. Which other park would blast a canyon to house an inverted coaster? Which other park would theme a ride to an boney alien which may or may not be dead? It's entirely Alton. And whilst Smiler's theme is certainly unique, any park can put a coaster in a concrete pit. Only Alton Towers would do something as bizarre and terraform to this level for Nemesis.
Nemesis is a ride I can daydream about, and be grateful that we have something so special in this country. The Smiler - I can't wait to see it go.
