i already have a zoom B3 that i use for most of my effects. i like it a lot. there's a few things about it that i wish were a little better though. i'm looking at the m5 for the octave effect, phaser, and chorus. i'm hoping someone that has/has had both could tell me if the ones in the m5 are better and if it's worth picking it up as an addition to what i'm already using. it wouldn't be my main effects unit. i'm really happy with the synths, filters, delay, flanger, etc in my B3 so it's not going anywhere. it would just be an addon to what i already have.