Before you go spending money on travel insurance, you might do well to check what coverage you have already. Your health insurance plan, for example, might very well cover you for any medical expenses you incur abroad. (My Kaiser plan does, and I've made good use of that on several occasions). Also, your credit card may provide some coverage. For example, my Chase United Explorer Card will reimburse me if I (or my travel companion, like my wife) get sick and have to cancel a plane reservation. I've taken advantage of that, too. And my homeowner coverage also provides for such things as coverage against identity theft.
Granted a plan offered through Allianz as some other company might provide some additional coverage, but you'll have to weigh whether an expense of several hundred dollars is really worth it to cover some situations that are extremely unlikely to occur.
So -- my advice is check the coverage you already have, and then make a decision as to whether you really need more.