Hi, I have been using Fisheye HC-3 , UWL-100 + dome for two years. There is no white balance control for this housing and so as for SR-12. And I think you better not to use any wide angle at all.The distortion is very obvious even with the doom when you zoom in halfway. This housing is only suitable for flat port, 5-10m with good ambient light, or macro with Fisheye LED video light. Yes, it is small and light, but any addition of wide angle with dome, with video light , you won’t enjoy diving because it is so negative underwater. Or, like me, DIY two big acrylic cylinder 4” x 6 “ to make the whole set up to float.
My conclusion, don’t invest any additional wide angle or video light. If you enjoy taking video underwater, buy another set of housing.
I am now using Aditech housing HC-9, with WP-80 wide angle, not expensive, really fast and accurate electronic white balance. Good full zoom performance with no distortion.
And Aditech housing float, can carry I Kg extra underwater. Too good for my two FAMI LED 200 video lighthead.
Now, I can enjoy taking video underwater so much.
Regarding the weight, hand carry the housing with you.