Crane stock and face mask

[iKiX]

I use a sansei face mask and with a standard fixed m16 style stock i dont really have any issues with using the iron sights, but with using a crane stock how do you guys think it will be? What would be the best red dot/acog/eotech style to allow me to use it should the crane stock prove to be a problem.

Cheers, iKiX