I' ve never shot a deer with one so I can' t comment on that aspect but Slick Tricks are the most accurate fixed head I have ever shot. They will hit where your field points hit. At any speed! I have intentionally shot them out of a mistuned bow and they still grouped with my field tips.
But at your speed a rocket steelhead expandable in 100 or 125 grain would blow through any deer even at 40 yards. I have found them to penetrate better than my fixed heads. I know that is hard to believe but thats based on my own testing. On 1/2 inch plywood the steelhead buried deeper than a muzzy,a slick trick, a steelforce, and a G5 montec. All shot on the same arrow, same bow and same distance. Repeated the test multiple times because I just couldn' t believe it myself but the results were always the same. The fixed heads all penetrated about 1/2 way the arrow but the steelhead buried to the fletching. Every time!