I like it. It works extremely well. Very fast and accurate. I didn't think that I wanted any of the extra non-guitar-tuning-related features, but it turns out that the built-in metronome comes in pretty handy and the tone generator has proven useful in assisting my kids with vocal pitch. I bought it primarily for electric guitar and bass, but also use it for flute, violin, trumpet, and voice. The built-in microphone is very useful and works much better than my old SonicResearch ST-122A tuner that this guy replaced.

Complaints:
I initially wasn't sure that I was going to keep it. It feels cheap and plasticky, and is much bulkier than I was hoping for. Changing settings/presets was not intuitive for me. I was able to make changes, but wasn't sure what I was doing. Ended up watching a handful of their short instructional videos on YouTube, and figured every thing out (but got sick of listening to the same excessively long intro music on every single video!). Also, I wish that the unit had a couple more characters for displaying the preset, or at least came with a list of what each preset was. Even the online list of presets could use more explanation. For example, if you want to tune an electric bass in standard tuning, you have "bAS" and "BSn" presets available. I haven't read anything official, but as far as I can tell, the only difference is that "bAS" is a sweetened/altered tuning, and "BSn" is an equal temperament tuning of the same notes. And "BSn" is "guided," meaning that it only locks onto the standard string tuning pitches (B-E-A-D-G).

Once I figured out menu system and filtered out the handful of tuning presets that are relevant to me, I grew to really like this unit. For me, the number one priority is performance, and the StroboPlusHDC nails it. It is accurate, fast, and easy to read (I have always favored strobe style tuners). Despite my seemingly long list of complaints (really, should have called them learning nuisances), this unit does exactly what I hoped it would and it does it very well.