They just released a bunch of updates to the F18 as part of the latest Beta patch (2.71 I believe). If I read this correctly this was the last update before the F18 comes out of early access. As far as tutorials, the F18 has the most of any aircraft. It seems to be the most popular because it can do almost anything (AA and AG) and carrier ops are really fun (and intense), especially with the super carrier. When it comes to jets I only own the F18 and though under powered at times I am glad I chose to purchase this one (I also own the P51D).
As a side note you can purchase an FC3 airframe for around $15. If you don't have much experience or don't want to spend days learning weapon systems they can be a great option. Then if you really like the game you can move up to a full fidelity module during the next sale.