Different tools for different jobs. When you buy a tool, you should know how you are going to make money from it. I use everything from low power portables to one that will suck your socks off. I use 175's with bonnets and pads, Brush Pro on some jobs. The truck mount is the ideal machine for doing residential work. With a truck mount, I can easily park in the driveway or close to the door, run 100 ft or hose on average and clean a 3 bedroom townhouse in 1 1/2 hours. If I had do the same job with a portable, I could do as good of a job but it is going to take a lot longer. Factor into, unloading the machine and accessories, either having to bring it up stairs or use extra hoses, plug in the machine, fill the machine, hook up the hoses and then reverse everything to pack up. Doing offices can be a pita with portable. Often you have only a 5 gallon hot water tank to provide hot water. With a truck mount, you just hook to a cold water supply and presto, you are cleaning with heat and power. Ever blow a breaker in a commercial building but the electrical panel in a locked electrical room. You have to clean a lot of carpets to pay for your truck mount but in the long run, it allows you the time to successfully clean all the carpet jobs you can sell. There are opportunities for portable only companies as well but you have to understand the limitations of your equipment. Although the carpet cleaning market may be saturated, it allows the premium cleaners to rise to the top, no matter what type of equipment they are using.