Yesterday i was on a music video shoot and got to steadicam op a steadicam flyer and a canon 5DMKII which was pretty cool, had to do some adjustments to get it balanced, used 3 extra batteries on the base the add weight and then changed the monitor over from the PAL steadicam standard one to the marshall with HDMI input so I could run straight out of the 5D. I was using the 17-40mm l series lens which worked really well for what we were doing.
The actually movement was pretty tough as it is sooo light compared to a xdcam for example and so keeping it steady was interesting!
But the amount of time you can op before getting fatigued is massively extended because of the reduction in weight.
I don't naturally have the steadicam build and so when I operate larger rigs it can be a bit of a killer but with the flyer I found I could wear it for 20-30 min at a time and not die! Which is great.