I used to have an older model Tasco Propoint ona Ruger Goverment .22 I used to have. I now have an Optima on the 10mm Glock I use for hunting.
I'll say that the older tube-style sights seem to be easier to use for hunting because I didn't run into much of a parallax problem with them. On my Optima, if I don't keep the dot pretty much in the center of the window, I can see some real interesting results. With the Propoint, I believe that I could get off-center a lot more without these affects.
IMSAO, I'd also guess that people who are used to magnifying scopes would probably be more used to a tube-style sight versus a window.
Oh, the other problem with the Optima's is that the window is plastic and kinda easily scratched.
All that being said...as long as I practice with it, the Optima still helps me whack deer quite easily.