I can tell you about the black ice..
Smooth as a baby bottom to draw, but still has good speed. No hand shock, barely needs a stabilizer to balance and has a rock solid wall.
Its just a great bow to hunt with. Small, lite, compact, yet forgiving.
I have not handled the Marquis yet, but it has the obvious differences, such as string stopper and roller guard, but also features a slightly more aggressive cam to bring speeds up a bit. I'm sure its every bit as awesome as the black ice, so you'll really have to try them to figure out which you like better.
The liberty is also another great offer from Diamond. Full wood grip, which is nice and warm on those cold sits, an even smoother draw than the Black Ice with the same great craftsmanship.
I dont think you can go wrong with any of their lineup.
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