I know the expense is prohibitive, but I have been shooting a glendale buck and feel that shooting at a life like deer target helps me more than shooting at block style targets. You can move the target to mimic the different angles a deer shows in real life. To me shooting at a block target does not give me that edge. When I shoot at the real thing it is just like what I do in practice. Just my honest opinion......
For Cossak, if you are shooting spitfires I highly recommend the Cabelas expandables as they are pretty much the same thing. I like the spitfires as well, but the Cabelas version is half the price. $19.99. And I have been using them for about three years and taken at least nine deer with them and have had no trouble finding the deer afterwards.