Judging from prior discussions and from US Customs online guidelines, there seems to be a significant level of ambiguity, fluidity, and individual caprice involved in the whole business. Imports that flow through without incident at one port of entry get snagged and caught in bureaucratic limbo at another. The personal experiences of various people are indicative of nothing more than that. And the practices at one port of entry will change from Monday to Friday, from morning to afternoon, phases of the moon, or whether the agent is happy or pissed when your item shows up. My experience with the Port of Los Angeles is that several weeks delay while sitting in Customs isn't unusual. Other people could have a completely different experience.