The throat of the Supreme and the Silvertip (at least mine) are almost identical in circumference at 4.25".
The Supreme is slimmer from side to side than the Tip. The face of the Supreme, being skinnier, seems to fit in the life-line of the bow hand very consistently from shot to shot.
However, I like the bit of palm swell in the Tip and of course the checkering keeps the bow hand firmly in place throughout the shot.
I think the Supreme grip promotes consistency like a metal riser. However, I prefer the "glove-like custom fit" of the Tip a bit more -- it feels like part of my hand.