I would expect a wider site window for longer riser.   What else?  Which would be smoother? Stiffer? Faster? Any did in finger pinch? More stable?
Thx in advance for responses
Mg

The shorter riser bow will have a longer working limb.  Therefore it would be smoother to draw and shoot.  I would give a slight performance gain to the longer riser shorter working limb bow.  Another difference would be mass weight the longer risered bow would weigh more.

Makes sense.  Heavier might be more forgiving because of stability too.
Anyone else???

Depend the bow design and the bower,depend you drawn lenght and the bow style (recurve or hybrid).  

If you add a bow quiver you could make up for the lost weight from the shorter riser, giving you the best of both worlds. Shorter riser would give you a smoother draw and I'd say add a little more performnce over the longer riser.

Caleb