I used Rage 3-blade last year and had pretty good luck with them. I am using 2-blade this year, but have not had a chance to test them out on anything other than targets. I have a friend who shot a nice buck 2 nights ago with the 2-blade and there was awesome devastation.
If you do a search on the forum I guarantee there is a ton of info. About a month ago someone posted some fairly gruesome pics of a deer that was shot with the 2 bladeI think.
I am always leery of changing anything in the middle of the season though. If you have something that works for you, stay with it IMO.