Alaskapopo has one opinion, perhaps a bit colored by his dissatisfaction with the rules changes. Full disclosure: I am a Certified IDPA SO.
Here is another:
IDPA
- Is more focused on concealed carry skills;
- Requires concealment because of concealed carry focused, but not during some courses of fire, depending;
- Limits shooters to guns that are more affordable and practical and the average Jane/Joe can buy, thus limiting "OPEN" and highly customized types of guns;
- Does provide great latitude in how to shoot the COF, but because of COVER penalties and SHOOTING PRIORITY penalties gives you an incentive to shoot by "slicing the pie" or near to far. You can shoot it however you want...you just live with the penalties;
- IDPA does not pretend to be training. It does allow you to practice your skills using cover and concealment and is more tactical than USPSA, but NOT tactical training, and, mainly because of safety issues, NOT a true tactical COF.
- One of the main rules that changed is that all reloads must be flat-footed and behind cover if cover is available.
USPSA
- Is more focused on pure competition and incorporates few tactical features;
- Does not require concealment;
- Provides divisions that allow for any types of handguns that are generally safe and ranges will allow;
- Does provide great latitude in how to shoot the COF, but has no cover or shooting priority penalties (You can choose to shoot them that way if you wish),
- Does allow lots of flexibility in where to stow extra mags, how to holster, more rounds in a magazine, etc.
BOTH IDPA AND USPSA
- Due to COF safety concerns restrict how close you can be when shooting steel;
- Due to COF safety concerns restrict going back to targets you have already engaged if doing so would create a muzzle violation or safety hazard;
- Have muzzle and finger restrictions while engaging targets, and may restrict full freedom of movement or moving with finger inside trigger guard;