For price, it depends on what you consider "comparable". If you're talking within $5 of Chinese prices, that's not going to happen. Most USA sellers buy from China (at the same price you'd pay on Ali) and then resell it for a profit while providing their own support and sometimes their own warranty. They're not going to go to that much trouble and risk to make $5. Some will for a $30 profit, though. To determine if it's worth $30 (or more) extra will vary heavily from person to person based on a number of factors, including: Familiarity with IP Cameras (ie. Are you good at programming IP devices or will you probably need to get assistance from someone that speaks clear English), how reliable is the Ali seller, how quickly do you need the item, how much of a gambler are you (ie. are you willing to risk losing $80 if the seller sends you a brick or would you rather spend the extra $30 or $40 bucks to have the legal option of filing a lawsuit against the seller if they send you a brick), are you looking for a standard/popular configuration (such as 4mm lens) or are you looking for something non-standard (like 12mm lens).
Point is, there's no "one size fits all"...If you don't know anything about IP cams or IP technology, then that's a point toward paying the extra to get support from a U.S. seller; if you are knowledgeable with IP devices, then that's a point toward saving money at Ali....If you want legal assurance that you're getting what you pay for, go with a U.S. seller; but if you trust your Chinese seller and/or would rather save money and take the gamble, then that's a point for Ali....If you want the camera within a few days, that's a point for fast domestic U.S. shipping; If you don't mind waiting several weeks, up to over a month, then that's a point for Ali.