As far as Begins masks go...
The "Deluxe" Batman Begins cowl made by Rubies (around $30) is fine. Its easy enough to slip on and fastens with velcro in the back. So yeah, while there is a slit running down the back of the neck, it at least stays closed.
-However-, the "3/4" Batman Begins cowl, also from Rubies (and closer to $20), has -much more accurate- facial detail. The only problem is that it only covers roughly 3/4 of your head, leaving the back and neck exposed.
I like both very much myself. They might not be the ritziest things in the world but they more than do the job. They haven't sustained any damage in the time I've had them, so they seem durable enough to me.
With -any- mask, try your best to find them in person at a Halloween store so you can get a good look at them and pick out one that hasn't been mangled. They don't look like much hanging from those cardboard tags, but they're fine once they're properly displayed and in shape. With ordering online, you never know what you'll get imperfection-wise (on the other hand, its less likely to have been manhandled by Halloween shoppers).
