The heater once turned on, heats up the water at a rate of 2 degrees per hour. You can set the temperature beforehand, leave it overnight or during the day while you’re at work, then come home and soak in your desired water temperature. As with other models, this Intex portable spa comes with an insulated cover to keep the water clean while not in use. The cover also helps to keep the heat in until the time you decide to soak.

And this is the biggest misunderstanding between the two. There is a huge debate on the durability of inflatable hot tubs, but the fact of the matter is that they are now built with materials that make them as dependable as portable hot tubs. The reason inflatable hot tubs had to improve on their design is because they are moved twice as much as portable hot tubs.
They don’t usually use real water jets, but instead use fans to “blow” the air around (also because of the 120 volt outlet), which causes them to cool down much faster than a regular hot tub. This cooling effect is only made worse by the fact that the materials they are made from lose heat much faster than the materials used on a regular hot tub. All in all, you aren’t likely to get more than 15 minutes to a half an hour of good heat out of an inflatable hot tub.