I fly the FS9 model (converted to FSX) in FSX all the time, with full realism, and have a blast with it - of course I use TrackIR, which makes it a whole lot easier to manage your POV out of the cockpit. I usually only put 40-gallons in it for every flight I do, but it may handle better with more fuel than that (while the ORA "Spirit" reproduction is very close, I think they only have something like a 65-gallon fuel tank in it (compared to the original 450-gallon capacity), since there are of course no plans to fly it across the Atlantic, and even then, you'll get a good amount of flying time - for this reason too, they had to put some extra weight in the nose to keep the center of gravity where it needs to be for best handling). From what I've always read, the "Spirit" must handle a lot like the other aircraft of that period, including the WWI types, with all of that wing area and very little rudder or vertical tail fin to speak of. Ken Cassens, who flies the ORA "Spirit", has a lifetime of experience flying those early teens and twenties era machines, so his descriptions on how it flies are based on his experiences with other types from that era and before - it might very well fly quite nicely compared to WWI-era fighters/trainers, but probably not so much compared to modern aircraft.
I've noticed, flying the sim version a lot, it is quite easy actually for take off and landing, as long you are able to set yourself up to see/realize what it is you're doing with every control input - the aircraft never does anything unexpected just by itself - when loaded for a normal flight, it gets up and goes quite well too, and if you land at the proper speeds, allowing you to three-point it, that tail skid brings you to a stop quite quickly, which is also very nice. The hardest part is just getting accustom to the feel in the 'air', which can be a challenge, detached from the sim as we are, and not actually 'feeling' what the aircraft is doing, but simply relying on the visual experience out the side windows and the turn/slip indicator on the panel. With such little vertical fin/rudder compared to wing area, the aircraft does like to skid around quite a bit, but you see that a lot with other types as well from that era and before, such as the WWI fighters, with all of their wing area and little tails. The aircraft does have elevator trim, which is quite effective (when the ORA "Spirit" first flew last year, too much weight had been put up front in the nose (based on their ground-calculations, it was the right amount in theory, but not in practice), and Ken Cassens had to quickly put full elevator-up trim on during the takeoff run - though the aircraft probably flew better with more weight up front).
An absolute fanatical clone of the "Spirit" (even more so than the ORA example), is nearing completion in Washington state, by JNE Aviation, and the plan is to tour the country with it next year, making all of the stops in the lower-48 that Lindbergh did originally, following the Atlantic crossing (2017 of course being the 90th Anniversary of the original flight). There is also another "Spirit" replica that is being built, called the "Spirit of St. Louis 2", which is planned to be flown across the Atlantic next year, retracing the same route, but this replica is being fitted with a Jacobs 755R2 radial, instead of the Wright J-5, modern instruments/avionics, and a larger fuel load than the original.
