Firstly I must say that they are very nice. As i'm sure others already know the detail on these snap fits are really good. Everything is on the sprue from base to body. Both the Nob and the terminator have as much detail I feel as there multi part brethren. Pose ability is limited due to the nature of snap fit but I did notice after taking the terminator off the sprue that the arms have pose ability. Its not much but you can add some personality to the model by posing the arms up or down.
Now you could of course get better posing by cutting the plastic pins and some green stuff to get more pose ability but that's more work then needed for snap fit. What is nice is according to the White dwarf issue you can interchange the parts they show the chest and head of a multi part kit on the snap fit model. So you could change the arms as well.
Well that was long winded but to sum up the snap fit models look great for being snap fit. Also for an Ork or Space Marine army I would think the assault on black reach box would be a good investment to fill out an army.