Hey Wetfeet. I think it depends on your bow weight and how sharp you get the Simmons, but a lot of guys get pass-throughs without too much trouble. Once you get above 50 lbs, it is pretty easy to get two holes in whitetails. All you need to do is avoid the bones in the shoulder and you are set.
That said, if you switched away from woodsmans to get better penetration you should probably stay away from the Simmons. I do know that Charlie Lamb swears broadhead sharpness will add pounds to your bow, if that makes sense. I tend to agree that razor sharp broadheads will penetrate far better than dull ones. All that to say, if you are confident in your sharpening skills(the grizzlies and woodsmans both razor sharp), and you still want the Grizzlies over the woodsmans, the Simmons may not suit you.