I have a taste issue with some vapes and assume it's a voltage issue. Is the Buzz a good choice for a first mod? The website is not very informative so whatever you can tell me about it would be great!! Like how do you change the voltage??

I haven't tried the ProVari, primarily because the Buzz came out first, and after a few months with the Buzz I bought a second as a back up that I've never had to use.
As it turns out, I don't change the voltage that much, but a variable voltage device is the only device that can hit the right voltage in the first place. 3.7 volts is too low, 5 volts is just a bit off from what works for me, and 6 volts is too much. I've had many mods (Buzz being the only variable voltage one I've had) and the reason I've had many mods is because I could never find one that performed the way I wanted it to.
Until the Buzz. I'd recommend it not only as a first PV, but a last PV. That's why I bought two, I was happy to have found something that completely satisfied me.
The Provari does look like it wouldn't disappoint though, essentially a fancier version of the same thing - but it doesn't look to have anything that would make me want to spend the extra $, it may have a few extra knick-knacks involved that could break, and I prefer the no-nonsense no-logo look of the Buzz. But that's just me. Definitely go with something that is fully variable so you can find the right voltage without buying a bunch of different devices.
Maybe I will settle on the Buzz but I'm not getting a voltmeter.
It isn't 100% sealed, so theoretically a juice leak could get into the device
lolThat "this" is pretty cool. Too bad it doesn't come in a 901/KR fitting or I'd buy one.