If you think any machine future-proofs you, you've got another thing coming
Whatever you 've got, you always want something else! But something like a prowler or phoenix will definitely bump you up to the next level mate.
Generally accepted rule of thumb is that a TM is roughly twice as quick as a portable, but all depends on what truckmount you're comparing to what portable!
If comparing a scorpion to a prowler the gap will be much smaller than comparing a ninja to a titan!
I've found domestic carpet work averages half the time it used to, that's comparing a ninja to a bluewave which is a mid-to-upper range TM in terms of power
Upholstery, not quite so much time saving if you pre-spray and agitate prior to extraction, maybe 3 to 3.5 hours with a ninja compared to about 2 with the TM. There's not as much donkey work the TM can take away on upholstery, seems as much more of it is in the preparation (at least the way I do it)
On big commercial carpet jobs, the time gap increases a bit more I've found. BUT the most important thing is you don't work yourself into the ground with a TM, you just crack along at a decent pace and you're nowhere near as knackered as with a portable. An RX-20 reduces the fatigue even less.
With a constant flow tool like a drimaster or sapphire, coupled with a good extraction detergent, you can also thrash through big volumes of commercial upholstery cleaning. A lot of the time you only need to pre-spray and scrub the bad parts, you can just do the rest with the rinse from the tool.
Don't even give a TM a second thought, once you get one you'll never look back. As your namesake Jeremy would say... POWERRRRRRRRRRRRRR
