I bought this pedal as a back up for some of my more expensive reverb pedals, but it has proven to be one of my favourites. It's extremely easy to dial in some great sounds and with the option of adding an expression pedal, e.g. the Boss EV-5, the RV-6 is really versatile.
I believe that some of the sounds (Hall and Plate) sounded better in the RV-5, but the Modulation and Shimmer settings are to die for. And when you think of the cost compared to some of the "boutique brands", this is an amazing pedal. And as all Boss pedals it's built like a tank.
I use this pedal in all my setups; both guitar, bass and synth. Use the Modulation for bass og the Shimmer for synth and you're in soundscape Paradise.