Since you ask, will go for the A70 anytime.
It seems to have a good manual setup, ISO as low as 50 and up till 400, full manual control.
Like the grip, that means sweaty palms you still have a good grasp.
Like the form factor (size, feel and weight), which means steady shots. dont like the "ladies handbag" type of tiny metallic cameras because holding them feels precarious, and many do not even have a slip of rubber for grip.
And I love AA batteries. they are cheap, you could get 3 sets of AA for 1 lithium-ion battery. Think how far you can go with 3 sets of the Sanyo 2100Mah.
As for image quality, all are using the same processor, i think the printout for 4R will be hard to differentiate. At 3MP, you could go up to >8R and still get good results. So image wise, i do not think you will get screaming differences between the A70 and the V3, perhaps slight difference with the S400.
However, I think the other criteria which i have little idea, is the responsiveness of all 3 cameras. Shutter release lag and AF. Then again, most non-DSLR digicams suffer a little in these 2 departments, some more than the others.