The Clever Dripper goes in and out of fashion. Right now it's... in. But that won't last. It is a little less glamorous than the entirely manual v60 (or other drip) method, and a little less alien than the Aeropress. But it’s a darling of home brewers for its repeatability, and I’ll try to elucidate why.
Consistency! The Clever Dripper is an ‘immersion’ brew method. Like the French Press or Aeropress, by pouring an amount of water onto an amount of grounds (and even agitating/stirring in some methods), you ensure that all the grinds receive relatively even exposure to the water compared to ‘pour through’ methods such as pour-overs or even espresso. This isn’t better or worse, but it is an acceptable method and, for the amateur, significantly easier to repeat. Pour-overs are harder to repeat as the preparer has to be careful to pour at the same rate and in the same ‘style’ - assuming the grounds were even distributed the same way to begin with. Espresso is a whole other basket case, of course.
No random temp fluctuations (down): When performing a pour-over, temperature stability is critical (consensus is somewhere between 88-93 degrees). Modern pour-over jugs have long spouts and steel construction, but even so the temperature at the spout can drop by 5-10 degrees from the beginning of the pour to the end. An espresso machine is more consistent (assuming it’s a good one basically hewn from a chunk of steel and brass). With a clever dripper, by immersing the coffee in one fell swoop, you ensure that all the grounds are exposed at the desired temperature. Of course the temp may drop during the brew, which may or may not be desirable (in my experience, it’s not a negative thing, but I haven’t found a way to keep the temperature always consistent in any method other than espresso).
Reliable and fairly easy to maintain: After years of on and off use, I find the valve on my Clever Dripper has suffered almost no wear and still functions perfectly. It is not a perfect seal (for example, if you try to do a cold-brew immersion coffee overnight, you’ll find about 5% will leak out), but it’s ‘perfect enough’ for short duration brews. Washing requires a rinse through. Note there are some parts of it that are basically impossible to get to - requiring you to take it apart (I haven’t) and then to use a toothbrush. I think I’d rather just replace it with a new one after a few years…
Cheap: How could I forget! - they’re very cheap: always available for under $30, depending on where you live.
Get one - it's hard to do wrong.