I do the same work as you do, and the best of the three is the R9 290X, the extra 1GB of Vram really helps. I have this card for reference and ha the same decision to make.
For the price of the galaxy GTX 780 Ti HOF, that is the best value for money card of the three.
If you need any other help, just ask and we'll gladly help.
sweet thank you! I'll go with the 290x then. I was leaning towards the galaxy HOF but if the extra vram helps then i'll gladly go with it, rather spend a bit extra to get more out of it.