There are a few good detailed reviews of the H2 on the net (such as GPLama's) so I won't bother with the details.
I spent a lot of time trying to choose between the Tacx Neo and the H2. Most reviewers mention the Tacx is quieter and maybe it is but I don't find the H2 all that noisy. I'm training in the garage anyway so it doesn't matter. While there is a bit of belt noise it's never that loud unless doing a max sprint effort.
What won me over in the various reviews was the solidity of the H2. It is rock-solid where the Tacx Neo appears to flex a bit. This is a very sturdy unit (lift with your legs when you're moving it around your pain cave!) I'm a larger rider and I don't notice any movement even when sprinting.
It works great with my two main control methods Garmin Edge 1000 (to ride a loaded GPX file) or Zwift on a PC with Garmin ANT stick. Out of the box, after spinning on a cassette and plugging it in, the H2 synced up with both systems easily and instantly. The only catch I found was that it may get confused and attempt a Bluetooth connection when Zwift Companion is simultaneously running on my phone. Just disable that option in the Zwift app and you're good to go.
Resistance works exactly like it should with no sudden changes in load unless you're working with a GPX file that's got noisy elevation data, for example.
One minor thing that I couldn't find mentioned before purchase is that the H2's freehub has a 1.85mm spacer included so you don't have to buy that separately.
If there's anything negative it would be the front wheel tray. It doesn't raise the wheel up enough for me (I prefer to be slightly elevated from level) and moves around a bit when riding. After the first ride I went back to my method of putting a thick textbook under the wheel.