This is an often recommended mic for DSLR filming. It does the job, and improves your sound recordings over the sound recorded in the DLSR itself. If you are looking for a cheap microphone to upgrade this is a safe one to buy. If you can spend a little bit more, there are better alternatives.
The body/chassis is plastic and feels a little bit cheap. The battery compartment takes a bit of force to open, which makes me afraid to snap something. The floating chassis does do a good job eliminating handling noise very well. The microphone is foam shielded to reduce wind noise, it works well. In my experience the usable distance is not too large, the mic gives the best results on 40cm to 1,5m distance. Further away the sound drops quickly to less usable levels.
This is one of those products you can't rate low because it does a good job for a really low price. Its it really great? No, not really but depending on what quality you are aiming for this is definately a good upgrade from using the camera built in mic. I use it for interviews on location.