Yes, the 18 can be "on rails" as you put it. Although I find it can also be like driving a big truck sometimes and other times like being a bee. So its rewarding when you can get the very best out of it. I definitely don't think it lacks character, its just where the extremes of its character lies that may not appeal to some. By comparison I had a love/hate thing with the SU27 in FC3 especially because sometimes it was an absolute joy to fly and then suddenly it'd basically be hellbent on killing you. Then you have the good old dependable SU-25 which is just looking for an excuse to kill you as soon as you try and push it.