AD8061 output voltage saturation different from spec?

I am using ADsimPE to simulate the AD8061. For some reason the site won't let me upload the schematic but it is just a simple gain of 2 with input pulse from 0V to 2.4V, +Vs=5V, -Vs=0V and resistor values of 500 ohms each from output to IN- and from IN- to ground.

The output saturation voltage vs output current is much different than what is indicated by Figure 7 in the data sheet. The output voltage only goes up to about 4.4V which is about 0.6V below the positive supply. The data sheet indicates that with output current <10mA the output should not saturate until at least +Vs-0.2=4.8V. I must be interpreting something incorrectly - please advise.

Thanks,

Jason