Found this short review of the Friction Power Supply. The review is ok(ish), says what is needs to I guess but I thought I’d link it because I bought one of these a few years back.
I pretty much bought it because it was small and I needed to make more space on the shelf under my workstation. It’s definitely small, it does a good job though and is pretty durable (being so light I’ve pulled it off my shelf a few times…), the only problem I’ve had with it after 3 or so years is that the dial slips a little which means you end up turning it a few times to adjust it, this only happens occasionally though. It may be that I need to open it up and tighten something, I guess I’ll check it out if it gets any worse.
I wouldn’t use it for tuning a machine just because I like to see things like the amps, duty cycle ect…. with this little guy you just get the volts on an LED screen, but if you’re putting together a convention or travel case or need to make some space then this little power pack is probably worth forking some cash out for (and it’s pretty cheap).