I'd go with the Deva, hands down. The automatic emptying and cleaning makes if a doddle to use if you have the water supply on hand. I've looked at both, seen the videos and have been seriously tempted by the Deva, It might be expensive, but it's only a couple (or less) 5x7 cameras and much less than some 10x8 cameras. I've spent half (or thereabouts) on a single camera, and as to the total expenditure on lenses...
Edit to add:
If I used colour, I would be much more interested. I admit that standing around for 16 minutes, inverting a tank after each minute for the first three then at three minute intervals is rather boring, and I'd prefer to let a machine handle it; but I can cope since there are relatively few chemicals and a manageable temperature to maintain with black and white.