Smiler varies between trains, rows and individual seats (inside seats are more comfortable).
Today was an utter mess operationally - the entrance plaza was a shambles, with no clear distinction between ERT and non-ERT guests, WM spent most of the day loading a total of 1 1/3 of it's 3 trains even when it wasn't broken down entirely, Nemesis on 1, Galactica on 1 station, Smiler on 3. Very long queues for all of the above, plus Thirteen apparently which I didn't even go near so I can't comment on.
I had expected to get on WM within an hour or so, giving time to do Smiler before Rita and Thirteen opened. In the event I was still in the WM queue when it was cleared at around 12.30, then waited 75 min after it reopened later on despite joining the queue half way between the shop and merge, which really isn't far. Finally a 120 minute wait at the end of the day, I think it must have taken them an hour or more to run off the fastpass and RAP queues, though the queue was still slow even after that due to it only running 16 rows across all 3 trains.