I've had the 14" aluminum riser a year now, and recently (3 weeks ago) received a custom made 16" riser from A & H. I prefer the 16 inch riser as personal preference since it offers a slightly larger window but mostly because it makes my bow 68". Now I can rest my binocs on top of the bow and they are at the perfect height to see out of.
This is the 14" aluminum riser, witha Predator camo dip, a Beavertail grip wrap and arrow rest.
This is the 16" riser, with a custom inlay of a bear scene scrimshaw. Larry did a really nice job on the inlay. Very talented man. Wood is Ligum Vitea, (Vera Wood) which is both oily and heavy. Actually heavier than water (it sinks).
Keep in mind that whatever the limbs are lised as, you'll subtract 2-4 lbs draw weight when using the 16" riser.