I test drove a 2016 CX-3 GT with HUD. On the CX-3, HUD comes as standard equipment with the GT trim level and is not an extra cost option. I havent driven a 2017 CX-5 GT with the premium package. I assume it has the same type of HUD display as the CX-3.
HUD: Is it worth it? To me, its not. Personally, I didnt like the speed being displayed on the windshield right in front of me and all the time. Im planning on getting a 2018 Touring model and Im glad HUD isnt available on the Touring model. Maybe fighter pilots need HUD but car drivers? Its redundant and unnecessary if you ask me.
In addition, I dont think you can turn off the windshield speed projection and you cant adjust where on the windshield you want the speed to be displayed. The premium package includes other features besides the HUD. Drive one and evaluate HUD yourself. Consider the other features as well and whether $1800 is worth it to you.