Phoenix broadheads by Red Feather Archery are what I currently have -- good price, too -- and soon I'll have some German-Kinetics SilverFlame XL broadheads (pretty pricey, though).
Here is a very helpful
Broadhead test comparing over a dozen different broadheads shot into different medium such as water jugs (to judge how quickly they drain), plywood, and... ribs covered in deer hide. There's several videos showing the different tests. The best penetrating heads were the fixed blade cut-on-contact heads.
An excerpt:
I did like the hellrazor it was a very consistent head. I have had people tell me they can't get it to fly but I didn't have any problems. Also the Phoenix did a phenominal job, and is the one that will be in my quiver this year. In the pork ribs test with my set up it hit 1 rib dead center and got the outside edges of ribs on either side of that so at least 3/4 of the head was in bone and then after hitting those thick pork ribs it still got over 18" of pentration. Some got more but none of them hit that much bone either. The best part was I could look through the hole that was left