Well, if the 7' above your roof is set in stone then the only thing (as far as I know) that the VP2 will do better than the Vue is to allow additional sensors such as soil/leaf moisture, solar, uv, ???, to be added to the station. If you garden or work with solar energy then the solar sensor would be nice to have, soil/leaf moisture sensor for gardening, UV...not real useful. So, if you feel like the Vue has every sensor that you think you will need then it will suffice for wind data.
I agree with CW2274 that placing the ISS in that lofty location will be problematical regarding maintenance/repair....especially keeping the rain bucket cleaned out. The new Davis units are shipping with the new buckets that have the bird spikes (make sure you get a current version) so that will help a little. In a populated, residential-type area most people have to compromise on their siting, it's somewhat of a "given". Even folks in the country have issues finding the perfect location and being able to elevate the anemometer up at the recommended height (33ft/10m). But, installing the ISS in a hard-to-get-to location is known to cause the "I'll do that next weekend" syndrome.
If it was my station, and it was mounted on the roof, I know that the biggest issue would be keeping the rain bucket clear. The birds consider it their own personal Porta Potty. But, other things happen, too. I will be working on my anemometer very soon (waiting on parts and for a very wet weather system to move out...also have the new style bucket coming), but mine is on a pole that is mounted on a 4x4 post via some swivel braces so a short ladder, undo one brace and loosen the other one and the pole will tilt down to the ground.
Think hard about the maintenance aspect of the ISS. But, for only wind, I feel both will give you more or less the same data...when placed in the same position. The VP2 will not have as much body/housing in close proximity to it as the Vue will....slim anemometer design versus the Vue's bulk of the entire ISS sitting just below the anemometer. Since your research is "wind" I thought I'd mention that last point...might make a difference if you data needs to be as precise as possible. But, everything is a compromise...we just do the best we can.
I'm curious, where was your Acurite situated?
Best wishes,
Ed