The gear that was used for this task. Nikon D300 w/ MBD10 grip, Tokina 10-17 lens, NN5 with RD16 and EZ-leveler II.

Before I get in to the main question here are links to the reference shots.

Shot1.
Shot2.

So yesterday I was in the camera store and and was eying the Nikkor 10.5 and the Tokina 10-17. For starters I hadn't read Ken Rockwells review on the 10-17 till yesterday. But even in the short time I used it, and I am not to picky sometimes, I didn't see any issues with it. So I like having options so I picked up the Tokina 10-17. The intent is to create a 360 pano with 4 shots, not counting up and down. So I get home and I am eager to try this lens out. I take a few standard shots with the lens and they look fine. So I start researching the settings for this lens. Not seeing where anyone had their exact settings for this lens and knowing the point will be near the focus ring I setup for try number one. Which is this shot here. I use two programs for stitching, Autopano Pro and PTGui. I take my first 4 shots into Autopano and it doesn't even detect a pano in the four shots. Odd I thought.. so I open them in PTGui. After I do a basic stitch without making any adjustments I notice the black holes you see on the left and right of the 4 different shots. Keep in mind I ball-parked the pivot point. After some playing around I settled on the settings used for the Nikkor 10.5 as best I could tell it looked about right. So the best I could get it is the result in Shot 1 above. Shot 2 is at approx 13mm with 6 shots taken at 60 degrees dialed in on the RD16. You will notice a stitching error on the right side of shot 2. I think that was from the weight of my flash moving the camera off center as I pivoted.

So... the questions I have are this. It looks like there is not a 180 degree FOV at the top and bottom in landscape or Right and Left in Portrait. Is that an accurate assumption? or did I do something wrong? I shot the pano shots with the camera on the arms in Portrait. Should I shoot the 4 shot 180 degree panos with the camera in landscape? Would I have the same results with the Nikkor 10.5? or do I need to get an 8mm?

I returned the lens the same day I bought it. Because as far as I could tell that lens wasn't going to work and the camera shop person that helped me wasn't familiar with the 4 shot 180 pano setup.