Dear Mr 49 - First of all, welcome to MLS! Sadly, I am the first to respond, and I am well-known as a total wet blanketter and all-round misery, so it will come as no surprise to read that I would advise you - a total beginner with live-steam as you say you are - to start with something a mite less ambitious than the biggest, best, and one of the most complex, locomotives that Aster have ever produced in kit form. My advice to you at this early stage is to look at the threads that have been posted about building this complex and expensive model. Building helicopters is a great pastime, fer sure, and when they go wrong they tend to fall out of the sky - at least a Gauge 1 live-steamer won't do that, but they are a lot more complicated than the mostly ready-to-assemble helicopter.
My own view is that you might dip your toe in the water by building the Aster Mike, of which there is a ton of information posted, not only recently, but in the recent past, and to check out the build documentation and 'how-to's' by folks who have built them. There is also a good deal going on the kit right now from a dealer whose name escapes me - again, on the thread.
I'm not saying that you are going to go wrong with the S-2 - a beautiful model and a very hard-charging hauler, by all accounts, but dropping $6000 or so plus taxes for a kit is a lot of money to fork out to find that maybe it's not quite what you thought it might be. You ARE going to need some serious trackwork to run it on - you don't actually mention that aspect of it, as it certainly is not a temporary 'patio track' loco by any means.
It's a great ambition to work up to an S-2, but IMO starting your live-steam hobby right at the top is a bit like learning to drive by buying a Formula 1 car.
Here on the forum, where we naturally have a number of Aster and Accucraft dealers who add their collective wisdom to those like me who are less-well-informed, but still highly opinionated. As a result, we generally get folks into the live-steam hobby the easy and far cheaper way - by building the Accucraft Ruby, or, in my case, recommending a Roundhouse self-assembly model. Sadly, apart from Aster's fine products, there are no Gauge 1 kits of US locomotives around.
Jump into the [very] deep end if you will - it's YOUR money - but I recommend a more gradual approach to the complexities of our great hobby.
tac