The first part of your question is for Nick but I think EXP uses the newest model you have selected.

I like to run each modal separately anyway so you know which is advising which action.

I like GFS or as you say HRRR for East Coast US.  Maybe if you say what area you;re in will result in someone popping up from there.

Your question points out the challenge of having several choices.  If they all align, great! But if they don't, it comes back to the navigator and his experience.  You can look for 'clues' if a particular model eg says the windshift will come early vs another model says it will come late.  Real time observations will guide your choice.

Hope this helps,
Ernie M

For the New England area the HRRR is pretty good and GFS if you want deeper into the future.

With a little time you can compare those forecasts with real data from
https://www.ndbc.noaa.gov 
eg plot on EXP the position for buoy 44008 (SE of Cape Cod).  You can right click on that spot  and click Meteogram to capture the forecast winds for certain times   Then as that time arrives check on the NDBC for actual wind recorded at the buoy. (ditto for other large NE buoys)

This will give you a confidence level to plan future races/trips using the Optimization feature.

And, I'm sure you know; make sure you consider the currents!!!

Ernie M