If you asked me, I would tell you that it would be better if HUD softwares like PokerTracker has never been invented. These softwares made gap between good and weak poker players smaller because they directly show weaknesses of individual poker players. That causes that winning players win less than they used to in the past.
Beside that, HUD software promotes TAG poker strategy which leads to the fact that poker fishes do not enjoy their game as much as they used to.
Simply said, risk of HUD software is that for many players poker is not as much fun as it was before. Anyway, HUD software proved to be a very useful tool and so it would be very ignorant not to add it to arsenal of your poker weapons. I believe that if legendary chinese general Sun Tzu lived these days he would definetely used it to know his opponents and beat them.
On the other side, do not think that HUD software can cure all your problems. It´s purpose is opposite. HUD software will show you your biggest leaks, where you lose most money and weaknesses of your opponents at tables. How you handle these valuable information to improve your game and take advantage against others is entirely up to you. HUD software like PokerTracker, Holdem Manager or Poker Copilot can be very useful and powerful tool for increasing your poker profits, but never do not stop thinking for yourself.
Remember that human brain is more sophisticated than any computer program and if you use your individuality and creativity to become better poker player you will be ahead of anyone who relies only on Heads Up Display software.
If you are not sure if these softwares can be useful for you and your game, simply download PokerCopilot and test it their full trial version for free for 30 days. During that time you can decide if it can improve your game and poker profits.