rleeI was using version 1.10 but have literally just upgraded to V2.0. I was shooting in XAVC-I, S-Log3 with the slo-mo at 180fps. Shutter speed was always 180 to the frame rate so I'm not sure why some shots would have been more jumpy than others, esp since some where shot directly after one another. Maybe there was something I missed while shooting, I always checked before shooting but maybe missed it a couple times, not sure. It was pretty much my first time I could get stuck into the camera. If you have the cam, or have any tips, I'm all ears.
Yea, v1.10 had a couple issues. For being so new though, it worked remarkably well for the camera's first firmware, but v2.0 is a vast improvement.
I prefer to shoot S-LOG3.cine. One reason, to put it simply, is that it's much easier to grade than S-LOG3 and you aren't really sacrificing a lot for it. For a better idea of the difference between S-LOG3 and S-LOG.cine check out this link-
http://www.dvinfo.net/article/acquisition/sonyxdcam/sony_sgamut_vs_sgamut3.html
In relation to the jumpy slo-mo, it is probably something on the post production side then, instead of an issue with the camera.
Also, were you using Cine-EI or Custom mode? This should help answer some questions with that as well-
http://www.xdcam-user.com/2014/12/ultimate-guide-for-cine-ei-on-the-sony-pxw-fs7/
Hope that helps!