On the first one I wanted a very dramatic look, on the second one I just wanted it to look cool 
and on the third one I wanted to try an unrealistic abstract style.
How did you do the one with the Car?
For that one I set up a fluid sim with a sphere at the bottom where the car should be as an obstacle. When I found a good frame I just aligned the car to look like the obstacle. With all of the reflections from the water the car looks more like it’s under the water.
These look nice, what kind of critique are you looking for?
Just anything that could’ve been done better. Mostly compositing.
The main problem that I see with the car picture is that the water doesn’t look realistic in a physics sense. For one thing, the water doesn’t look right coming straight down in the tube shape, but it also needs to be a higher resolution. Some of the water drops that come off the car look almost like diamonds or something since they have sharp edges. The scale of the water may also be off. I won’t even comment on the texturing of the car :). In terms of compositing, the problem that I see is that there aren’t enough things for the glare streaks to form off. Turning down the threshold might fix that. The glare streaks themselves also look too uniform. One thing you could try is turning the number up to eight, and/or changing the angle to 30 degrees. Adding a small fog glow may help as well. If you do add more glare streaks, you will probably want to turn down the size of them too.
To be honest, you need to post before/after pics if you want people to critique compositing - else it’s hard to spot what was made… Well, some things are obvious, like flares, but you know what I mean… 
(Not my image, but makes my point. And also scares me a bit. :D)
Oh, I know that feeling. This is why I party like once a year nowadays, hehe… ;D