Ronne,
The Ultralight doesn't seem to measure up to the plain old VX 11 for brightness, and by more than the difference in objective lens size would indicate. Check both of them in dim light and you'll see. In bright daylight everything works. If I remember correctly the VX 11 is fully multicoated while the Ultralight is multi-coated on the outside lens only, much like the VX1. Whatever the reason, the difference is apparent. Size and weight doesn't seem to be an issue since you are considering the Conquest, but if you are trying to trim things down the 2.5-8 VX111 is a great scope. It'll absolutely blow a ultralight away, but so will the Conquest. Out of the two you listed I'd take take the Conquest in a heart-beat, but it isn't really an apples to apples comparison.
