Here is my first attempt at using Fusion 360 to model the Cerberus Twin Pistols from the game and anime Gungrave. I had previously modelled these pistols in 123 Design but was not too happy with the scaling. This model is already scaled to be full sized and I went over the grip design until I was happy with how it felt. Go ahead and print two, paint and show them off. I am 5'7 and it fits in my hands perfectly but if you are bigger I would recommend cutting the grip in netfabb and doing a test print and scaling it if needed.
Update:
I was finally able to print half of the model and noticed it was a little thick. I have uploaded an updated version that is 28mm thick to make it more realistic and easier to grip.