The Al, Silo (24 fret) and Silo Spec (22 fret) are all really nice and the necks play similarly. It's a decision first whether you want the 24 fret range at the expense of pickup placement or not. Then, if you want 22, you really need to play both to decide which body you feel better with. The silo (and silo spec) are comfortable and easy to play while the Al is that and more, in my opinion. I find that with the Al, I absolutely have to have strap locks to feel safe.
To me, the necks feel the same on all of them. All are perfectly balanced and play beautifully. The nice thing is that whichever you pick up, you're going to be happy with your choice. You're deciding between the best of the best.