I have both and the reason I will say the VPA is because of the Non-vented design,, like a 2 blade that sucker should slide right through...
I personally believe that vented heads catch on flesh and bone upon penetration and during pass-thru (or almost passthru) it may not be significant with 50# + but with anything less it does and its my opinion but the birth of "non-vented" 3-blades has changed alot of things for light weight shooters like myself..
other than that I say its based on what you can sharpen,, the VPA will be easier and the simmons I think you need a bit of experience to get them right and they are tricky for me,, centaurs are worth a look too but again tricky to sharpen at first and another favorite of mine for light weight is Abowyer which just needs a few strops on cardboard or denim and its a brutally sharp head.