Night & day difference
Portable; lot more time, and the carpet takes a long time to dry. The water a portable uses can only be as hot as the water from your faucet, usually about 120°. However by the time it leaves your faucet, is put in the machine, and cleaning begins it is much colder.
Truck Mounted; The water in a Truck Mount is heated constantly to over 280° That’s a lot more chemical action and a MUCH better clean. The increase in heat helps to more effectively break down soil, grease, and other spots for more complete cleaning.