I've used the vertex batt grip but finds it too plastic for me. Have changed to the original and even it's not stated as weather proof it just feels more sturdy and solid.
thanks for the feedback, i am ok with the plastic feel....i am only more concern with the sensitivity of the buttons.
I have been using 3 different 1-series bodies in the last 8 years, so i guess nothing will be more solid than its fully metal body with build-in grip
However, I noticed that even the build-in vertical grip on 1-series has different sensitivity which bothers me.