I bought this when I was on a tight budget to get some dirt for my bass. I couldn't find a dedicated bass distortion pedal in that price range that I liked, so I tried this out. It works perfectly fine, and has more than enough gain, without losing too much low end, which is always a risk when distorting a bass. Just add a bit low end on your eq and you should be fine. Other than that, the build quality is really great. Not made of the same flimsy plastic as some discount brands tend to, this is build like a small tank, so you don't have to worry about breaking it. While I havn't tried to use it with a guitar, I can certainly recommend it for bass, especially if your budget is tight.
This is an inexpensive 'interpretation' of an OCD pedal, a rather popular overdrive/distortion pedal which is about 4 times the price of this.
Firstly why are OCD pedals so popular? Well because it's a very versatile pedal that can do a (fairly) clean boost or can reach a great Hard Rock/Metal drive. In front of a good tube amp you can use it like a souped up tubescreamer (which is a good analogy for the pedal as a whole) to push the tubes into overdrive. It's fairly transparent (in that no matter how much it's distorting you can still her the notes and chords without it turning to mush). Also when set right it can be very touch sensitive (especially for bass) in that when you play gently it'll stay clean but hit harder and it'll overdrive. Another added bonus it that it doesn't really lose any bass frequencies when you use it on bass.
Secondly how does it directly compare to an OCD? The short answer is very well indeed. It managed to capture all the essential OCD characteristics mentioned above. No, you are not going to get the same sound from an OCD and the Ultimate Drive with all controls set to 12 o'clock, you will need to tweak the Ultimate Drive's knob a little to get the same tone and on the whole I'd say the Ultimate Drive is a little darker sounding (on both low and high settings). The artwork on the Ultimate Drive will also divide people, I don't mind it but I can see why many wouldn't be able to get past that. It does feel like a colossal misstep putting such dividing graphics on this pedal.
In summary It's a great OCD clone for a fraction of the price, providing that you can live with the artwork.